Late November through December Long range forecast.

 Some of you may be wondering, "What in the world is going on?".  Well, I've got to tell you, I'm wondering the same thing.  Over the past 20 days, most days have seen above normal temperatures.  Truth be told, we have seen some pretty chilly days in between these warm periods.  Even this week, most computer models are forecasting a major ridge to form over a large portion of North America for the holidays.  This would cause a relatively warm and humid air mass to surge northward into a large chunk of the United States.  Along with this warm air mass, sunny conditions will prevail for Thursday and possibly Friday.  As the polar jet stream is very strong this year, the ridge will shoved out just as fast as it came in.  By Friday Night, clouds will be on the increase, ahead of the next strong storm system.  This storm system will develop quite rapidly, as a major trough develops in the Plains and surges eastward.  According to the GFS model, heavy rain and quite possibly thunderstorms will likely develop by Saturday and into Sunday.  During these days, temperatures will rise into the mid fifties, much above normal levels.  The storm system won't stop there.  After the surface system leaves, a rather large upper level low will develop and remain for several days, bringing colder air and possibly areas of snow, bringing the first accumulating snow of the season to many areas.  After this it is unclear what will happen, but the GFS is forecasting that the AO will plummet to negative values for the first time in several weeks.  This may cause a major trough to form for the first and second weeks of December, bringing widespread snow and cold to much of the Central Plains and East.  With all of that cold air in Canada, I'm sure it will spill southward into the US.  This would make the weather pattern eerily similar to last year.  In fact, according to the latest run of the GFS model, towards the beginning of December, that upper level low mentioned earlier, will likely cause multiple storm systems to form and swing around it, also drawing in very cold arctic air to start the season off.  With low upper level height anomalies, combined with surface cold air, and plenty of moisture to work with, I'm sure that we will see quite a bit snow for the first two weeks of December.  As for the rest of December, if the AO and NAO remain negative, and the PNA remaining positive, expect cold temperatures and frequent bouts of snow to continue even through Christmas.  Unfortunately, I don't believe any major storms will likely form this period, as most of the storms will traipse up the East Coast.  I will keep you updated as December gets underway.
   There is one thing I do want to touch up on is dealing with the current La Nina.  The values I want to speak about are the SOI values, Southern Oscillation Index.  The Southern Oscillation Index is determined by taking the difference of sea level pressure readings from Tahiti and Darwin, Australia.  If this difference (Tahiti-Darwin) is negative, usually this correlates to either an El Nino or weak La Nina.  If this difference is positive, usually this means that either a weakening El Nino exists or a rather established La Nina event is underway.  If values are either very high or extremely negative, this indicates a solid ENSO event is underway.  Today, the Climate Prediction Center released their weekly analysis of the ENSO.  They found that SOI values are only about 10.1, which is pretty modest for an expected strengthening La Nina.  Some meteorologists are pointing out that they may need to revise their winter forecast, due to the SOI values being much lower than last year's.  I really don't agree with this, mainly because first of all every ENSO event is different so SOI values will range differently.  Second of all, generally second year La Nina's are usually weaker than the previous La Nina, with generally weaker SOI values.  Also, during east and central La Nina events, SOI values will be weaker than normal because of the fact that the most dominant weather influence will be located farther east.  When I look at how strong a La Nina is, my first index will not be SOI values.  I will first look at sea surface temperature anomalies across the equatorial Pacific.  Currently, anomalies are between one and three degrees Celsius below normal, indicating a moderate La Nina is already underway.  The second factor I look at is 850 millbar and 200 millibar wind anomalies.  If the 850 millibar mean wind over the equatorial Pacific is stronger than normal from the east, this means the trade winds are stronger than normal, indicative of a persistent La Nina farther east.  Right now, 850 millibar winds are stronger than normal from the east over the Equator.  If 200 millibar winds are stronger than normal from the west, this is also indicative of a La Nina because higher pressure aloft is located over Indonesia during a La Nina, and lower pressure aloft is located over the equatorial Pacific, meaning the winds will blow strongly from Indonesia to Peru.  This is what I have been observing over the Pacific Ocean.  I believe with these factors in play, plus a favorable MJO (I will explain MJO in another blog post.) in December, has lead me to believe in the strengthening in the La Nina and SOI values during the month of December and peaking in February and March going along with the CFSv2 computer model's forecast.  Other things such as NAO, AO, and PNA, have made me shaky with this winter's pattern, as they have not been consistent with many forecasts in the month of November.  We will have to see if the GFS and ECMWF are right in their forecast for a change to a negative NAO/AO along with a positive PNA.  If these factors do not turn as they are forecasted, expect a winter that is not as cold as was originally expected, with most of the cold air bottled up over Alaska, Canada and the Northern United States.  The good thing is that if these factors do not come into play, if it is not as cold this winter, expect heavier precipitation, and a greater chance for a very stormy and snowy winter, just like the Farmer's almanac says.  According to extremely long range forecasts, this may be our last hurrah winter, as next winter there is expected to be an El Nino in the Pacific, making it very unfavorable for snow around here.  In fact, next winter, we may say a return in Nor'easters and East Coast snowstorms, while the Midwest and Northern Plains is snow starved.  With the forecast through December 2011, I will keep you updated if something changes.  Other than that, this is the official forecast.  Stay tuned.

Forecast Update

According to the latest 06z GFS run, a rather large area of Northwest Ohio and Northeast Indiana may see as much as 1.5-2 inches of rain from the storm on Tuesday.  Depending on where the heaviest band of rain sets up, this forecast may verify.  But the last several runs of the GFS model have shown the storm trending slightly southward, bringing the heaviest rain south of a line from Auburn to Toledo.  If the models continue trending south, I will drop this line to Fort Wayne to Toledo.  Another than that, it looks like skies will be clearing out Wednesday, with partly cloudy skies by afternoon.  Temperatures will be rather cool as the front moves through the area, with highs only expected to hit the low 40's and possibly upper 30's, if the cold front is strong enough.  By Thanksgiving Day, an upper level ridge is expected to build into the area, bringing above normal temperatures once again in the lower 50's to lower 60's.  Skies will also range from partly to mostly sunny.  By Friday, the ridge will have moved so that southerly flow develops aloft helping to warm surface temperatures.  If the warming is strong enough, I expect that temperatures will reach into the lower 60's, with increasing clouds throughout the day.  By Saturday, a major trough will develop in the plains, bringing stormy conditions back to the area.  According to the GFS, heavy rain and thunderstorms appears likely Saturday into Sunday.  THIS has remained consistent for the past several runs, which makes me think there might be a major storm system this weekend.  At the end of the storm, there looks to be snow developing, with colder surface and upper air temperatures.  This snow could turn heavy enough for our first accumulating snow of the year.  The greatest snowfall accumulations will occur north of a line from Fort Wayne to Toledo.  But remember this is a week from now, so this all may change by then.  After this I expect several major troughs to develop across the Midwest, bringing widespread cold and snowy conditions with each shortwave that moves around the base of these troughs.  Hopefully, by later this afternoon, I will release my long-range forecast update for December, as things look pretty interesting for next month.  Stay tuned for further updates.

Official Forecast through Wednesday. Forecast Discussion.

Official Forecast from the Forecast Center

Today: High 53. Temperatures will continue climbing slowly, with increasing winds and cloud cover throughout the day.  Mostly cloudy to overcast.  A chance of scattered light rain showers during the afternoon.  Low pressure system moves east-northeast near Northern Illinois by early evening.  Winds from the south at 20-25 mph in the afternoon. Stronger gusts possible.
Tonight: Low 47. Temperatures dropping very slowly as warm air advection increases in the mid levels.  Winds will begin to subside overnight, with winds from the southwest at 10-15 mph.  Chance of scattered showers as the low pressure system moves northeast into Canada.
Sunday, November 19: High 52. Cold front begins to move through tomorrow. Temperatures dropping through the afternoon. Winds from the west-southwest at 15-20 mph. Chance of rain and showers throughout the morning and early afternoon.  Overcast.
Sunday Night: Low 38. Cold front has moved through completely.  Showers move out of the area.  Skies still remaining mostly cloudy to overcast. System redevelops in the south towards the overnight hours. 
Monday: High 48. Skies remaining overcast as storm system redevelops in the southern Mississippi Valley.  Most if not all of the rain will remain south of the area, unless the storm system redevelops farther north.
Monday Night: Low 37. Skies mostly cloudy to overcast, as storm system begins to move northward.  Rain chances increase through the overnight hours.  Steady rain develops north of the warm front.  Winds increase from the east and northeast as pressure gradient tightens.
Tuesday: High 46. Skies overcast, as storm system moves northeastward.  Steady rain ahead of the warm front moves across the area, with some pockets of heavier rain.  Winds increase even more from the east.

Tuesday Night: Low 31. Skies overcast before midnight, becoming mostly cloudy to partly cloudy by the early morning hours.  Chance of rain or snow in the early evening.  Winds diminishing from the northwest.
Wednesday: High 44. Partly cloudy to mostly sunny.  Cold temperatures remain after frontal passage.  The next storm system develops over the Rockies, to affect the area by Friday and Saturday.

Forecast Discussion

During this time, I believe it will be almost always cloudy through at least Monday.  According to the latest GFS prog., the storm system that was originally thought to head through the Tennessee Valley, will move more northward than was originally forecast.  This is because the southeast ridge will be redeveloping after today's storm system moves through, in association with a positive AO and positive NAO regime.  Today through Sunday, showers will be scattered and light in nature, along with gusty winds today, and diminishing weaker winds tomorrow.  The current storm system will move through the area later tonight, bringing with it scattered light showers around here, and a heavy snowstorm in Wisconsin and Minnesota.  The storm system and its associated pressure gradient, will also move out of the area tonight, causing the diminishing winds.  Not much clearing is expected Sunday, as showers are still anticipated in the morning hours, with only mostly cloudy skies in the afternoon.  By Monday, the storm system will redevelop in the southern Mississippi valley, and lift northward.  It's associated warm front will cause clouds to increase once again, but the rain should remain south of the area.  Monday night, if the storm system does make a more northeastward turn, then expect rain to develop overnight Monday.  If it does not, expect a few showers on Tuesday, and blustery winds, along with dropping temperatures.  Tuesday, if the storm system makes the turn to the north, I would expect steady rain with a few embedded thunderstorms north of the warm front.  Heavy rain is even possible, with an inch or so possible according to the latest GFS forecast.  After Tuesday Night, expect clearing skies, and much colder air to infiltrate the region.  I would even expect temperatures to be colder than what I'm forecasting right now, as these temperatures are based off the GFS model output, which has had a warm bias.  Wednesday into Thanksgiving Day, expect temperatures in the lower 40's, and nighttime lows in the upper 20's and lower 30's, under clear skies both days.  By Friday, temperatures will be rebounding again, in advance of a potentially much stronger storm system, which would bring heavy rain to the area next Saturday and Sunday.  Stay tuned for further updates.

Posting

I will be posting a five-day forecast soon, so stay tuned.  I will be starting to post more often than I have been.

Detailed Winter Outlook

After listing off my reasons for the winter forecast, I will give a month by month outlook on what will likely happen this winter, including region-by-region forecasts.  In general, wet and below normal temperatures will be persistent across the northern United States, while the South and Southwest will bask in sunshine for large parts of the winter, allowing for the Texas drought to re-expand.  Across the Northeast and Mid-Atlantic states, I expect them to start off with below normal temperatures and frequent snowfall, but by late January and February, I expect a major warming trend, while the storm track remains over the Ohio Valley.  In the Central Plains, I expect that frequent bouts of cold will hit the region, but precipitation and snowfall will be near to slightly above normal.  Now for the details.

(Disclaimer : This forecast is subject to change and it could change drastically.  Do not use this as a guide to the winter, as it may be wrong and you may solely be disappointed.)

November:  I want to start out with the month of November, mainly because I think that unlike last year, this year's winter may start out by mid-November.  November is looking a bit iffy for a forecast, but it looks like below normal temperatures will prevail across a good chunk of the United States, as the NAO goes negative by early to mid November.  Many regions especially across the North Central Plains will likely see a couple of snowstorms during this time, while other parts of the Great Lakes and Ohio Valley will likely see the start of the Lake-effect season, especially after mid-November.  There may even be some synoptic scale storm systems that bring accumulating snowfall to the Ohio Valley during this time as well.  In the Northeast, this may be the perfect time for a Nor-easter to form, even though it will likely not be a snowstorm.  Across the Southern United States, I expect near to below normal temperatures, along with below normal precipitation, causing the drought to intensify.  Along the west coast, near to above normal precipitation will be the rule, as an active La Nina pattern settles in.  Temperatures will likely be near normal to above normal.
December: During the month of December, I expect that winter will really set into the U.S., as bouts of arctic air and heavy snow fall across a large part of the East and Midwest.  I expect temperatures to be much below normal (5-7 degrees below normal), from the Northern Plains, southward through the lower Great Lakes.  This region of extremely cold air will cause the predominant storm track to follow the Appalachian mountains and the East Coast, allowing for the formation of a couple of Nor'easters, though not as severe as last year and the year before.  Therefore I expect precipitation to be above normal in the Ohio Valley and lower Great Lakes east of Chicago, towards the East Coast, while snowfall will likely be above normal along the major east coast cities and in the Ohio Valley.  Snowfall will likely be much above normal in the Lake-effect snowbelts.  In the Southeast, temperatures will likely be below normal for this part of the winter, bringing the only chance of freezes for the season.  Precipitation will likely be near normal to above normal which may help drought conditions some.  Across Texas and Oklahoma, there could be some major ice storms along with the cold air, while southern Texas will likely above normal warmth and dry conditions.  In the west, I expect above normal precipitation along the entire coast, and also some parts of the Southwest.  Heavy mountain snows will be frequent as the Pineapple Express sets up shop once again this winter for a time.
January: During January, I expect temperatures to warm quite a bit as a weak southeastern ridge develops across Florida.  This warmth should cause near normal temperatures along the eastern coast, with above normal rainfall and an increase in ice storms, especially in the Mid-Atlantic and lower New England.  In the Ohio Valley and Great Lakes, I expect the cold temperatures to hold on, causing the temperature gradient to increase between the East Coast and areas west of the Appalachians, which should cause a very strong jet stream, and the potential for several blizzards and snowstorms especially from Chicago and Detroit southward towards Indianapolis and Cleveland.  During this time, Lake-effect snow will dwindle especially around Lake Erie, as the lake freezes over quickly.  Across the North Central Plains, very cold conditions will prevail, along with frequent snowfalls from Alberta Clippers.  In the South, conditions should hold dry, with warm temperatures prevailing.  This holds true for Texas and the Southern Plains.  In the Southwest, very dry conditions will be present, as a ridge builds in this region also, along with much above normal temperatures.  Along the west coast, I expect temperatures to be near normal, but with above normal precipitation north of central California.  In the mountainous regions, expect above normal snowfall, as frequent heavy snowfall arrives in the mountains.
February: February should be the most dangerous month, as in heavy snowstorms for the Ohio Valley, Northern Plains, and Great Lakes regions, as I expect one or even two snowstorms to dump 1-2 feet on these regions.  Temperatures during the month of February should cold but could moderate by the end of the month.  Along the East Coast, conditions will probably be slightly drier than normal, as the storm track is displaced farther west from the region, and temperatures also be mild especially in the lower Mid-Atlantic states.  Across the majority of the south, I expect below normal precipitation and above normal temperatures, with the exception of Alabama and Mississippi, who could see a very active start to the severe weather season, especially later in the month.  In the west, I still expect a repeat of La Nina conditions, with frequent heavy rainfall, and frequent heavy mountain snows.  In the northern plains, I still expect a continuation of the cold, but with more snowfall than in previous months.
What this means for Northwest Ohio and Indiana: December: temperatures will be much below normal, with frequent lake-effect snows west of the area, with some lake effect snow affecting our area.  December may seem dry, until a major storm at month's end could bring copious amounts of snow to the area, especially in Northwest Ohio.
January: temperatures moderate some, not as cold as December, but still below normal (2-4 degrees below normal). Clipper systems will be more frequent in the beginning of January, but will transition into major Colorado lows and Gulf lows, that will bring frequent heavy snowfall by the end of January.  Lake-effect snow will likely dwindle, unless Lake Michigan does not freeze over.  Major snowfall amounts.
February: temperatures will continue to moderate as storm track shifts westward slightly.  Once again, I expect major snowstorms to hit the area, with maybe a snowstorm bringing a good 1-2 feet of snow to the region.  Ice storm frequency may increase by months end.  Temperatures will be slightly below normal to near normal especially by month's end.

Technical Winter Outlook Discussion

As many of you have probably read my winter forecast, I expect you have a few questions as to why I'm predicting what I am.  In this discussion I will give my major reasons for the forecasts, and a few other almost non-significant reasons as to why I made this forecast.  I am also including month by month outlooks, which will give details on things such as temperature, storm potential, snowfall amounts, and any warm ups.  By mid to late November, I will have a refined forecast, which will explain the month by month setup even more, along with storm track potential and when we can expect our first major winter storm in this region.  For now, let's get on with the discussion.
     The first major factor (and probably the most important of them all), is the fact that yet another La Nina is developing in the equatorial Pacific.  Currently, the Climate Prediction Center has upgraded their La Nina Watch last month to a La Nina Advisory this month in their latest ENSO outlook.  According to the latest analysis, the CPC (Climate Prediction Center) explains that the current La Nina is not near as strong as it was during September of 2010.  This proves the fact that this year's La Nina will probably not be as strong as last year's.  But over the last few weeks, La Nina conditions have been developing very quickly, with current La Nina conditions at about -1 degrees Celsius, which is way below September's ENSO index, which was only -0.6 degrees Celsius (note, when I refer to negative degrees celsius, I mean below normal and not as an actual temperature.  Actual temperatures in the equatorial Pacific are about 18 degrees Celsius.).  This value of the ENSO index indicates a border-line moderate La Nina.  According to the latest underwater temperature anomalies, there is still a very large region of much below normal water temperatures upwelling to the surface from about 100-200 meters below the surface of the ocean.  Most of these below normal water temperatures are occuring in the eastern and central regions of the Equatorial Pacific.  I will explain the significance of this later in the discussion.  Along with the factors that are promoting La Nina, I expect still declining SST anomalies, allowing for the strengthening of the La Nina.  I would expect the La Nina to level sometime in late January 2012 or early February 2012, at a peak of about -1.4.  In fact, this value may change because according to several of the NCEP's climate forecasting models, values may reach or exceed the ENSO index value of -1.5, with the CFSv2 forecasting a peak of about -2.0.  A value of -2.0 would indicate one of the strongest La Nina's on record.  But I really think the CFS's idea of this low of a value is almost farfetched, as current ENSO index levels are not nearly as strong as in 2010 at the same time, and we leveled off just before we could reach Strong La Nina values.  So, in conclusion, I expect the peak of the La Nina to be at -1.4, which is the exact same as last year.  Now back to talking about what east based and west based La Nina means.  In a west-based La Nina, which hasn't happened in several years, the coolest and most concentrated cool waters are located over the western equatorial Pacific, is almost similar to what happens during an El Nino.  Generally, west-based La Ninas cause a very strong ridge to form during the winter months over the East.  This causes much above normal temperatures to extend back into the Plains states, who would normally bring significantly cool temperatures to the plains.  During west-based La Nina winters, the Ohio Valley and Great Lakes would see plenty of precipitation, but not much in the way of snow.  They also tend to reduce Lake effect snowfall amounts.  During east-based La Ninas, widespread below normal temperatures occur over much of the U.S., excluding the Southeast and Florida.  Precipitation is also above normal from the Great Lakes and Ohio Valley on toward the East Coast.  Here are some maps to illustrate what I just explained.

z

Therefore, since this winter's La Nina is east-based I believe that temperatures over most of the Northern United States will be below normal throughout most of the winter.  But making a forecast just based on one variable won't do you any good.  So I went ahead and did research on the NAO.  As I have explained in past articles, the NAO stands for the North Atlantic Oscillation, which indicates that it has to do with the wind patterns across the North Atlantic.  How the Climate Prediction Center determines the daily NAO is by taking the 500 millibar height difference between the Azores and Iceland and comparing it to normal.  If the 500 millibar height difference is large compared to normal, the NAO is considered to be positive.  During positive phases of the NAO, the storm tracks shifts northward, because there is such a large difference in air pressure, the jet stream is very strong, allowing for many storm systems to form over Iceland and make their way into northern Europe.  Generally, winters and summers with a dominate positive NAO will cause much stormier than normal conditions over most Europe in both seasons.  A negative NAO, indicates that the 500 millibar geopotential height difference is smaller than average and the difference can sometimes be negative in some extreme situations.  This situation allows the jet stream to take a more southerly route across the United States and a southerly route toward Europe.  In these situations, the jet stream is weaker across the Atlantic, and causes extended cold, dry periods across all of Europe, and across the United States, the weather tends to be much colder than normal, and it causes a very snowy, stormy weather pattern across the Eastern U.S.  According to trends in recent months, and over the last several years, I expect the NAO to continue a downward trend and become more predominantly negative during the winter months, allowing for below normal temperatures and above normal snowfall throughout much of the east.  Scientists have also studied another index that strongly correlates to the NAO.  This index is the AO.  The AO stands for the Arctic Oscillation, and refers to the wind patterns and temperatures in the stratosphere over the Arctic regions.  When the AO is positive, this indicates that stratospheric temperatures over most of the arctic region are much below normal.  Much below normal temperatures over the Arctic create strong westerly winds in the Arctic stratosphere due to the large temperature difference between the poles and the equator.  With a positive AO, atmospheric blocking in lower layers of the atmosphere is reduced, allowing for an extremely amplified pattern with a strong jet stream over the Atlantic.  When the AO is negative, stratospheric temperatures over the Arctic are much above normal, causing above normal heights and weak easterly winds.  These weak easterly winds cause a ridge of high pressure to form in lower layers of the atmosphere.  This ridge of high pressure generally located over Greenland, will cause a road block in the normal westward wind flow.  The jet stream will move so that there is a major trough over the east, and when both the NAO and the AO are negative, this can create the potential for major storms across the East, especially during the winter season.

In actuality, I have read several articles about research being done on the NAO.  They believe they have found a non-trending multi-decadal oscillation of the NAO.  They have found that the NAO seems to have a thirty year cycle, going from mainly negative values to mainly positive values.  They have found three such periods in the known record, extending back to the 1920's and 30's.  From 1925 on to the 1950's, there was a positive period of the NAO, where only a few times was the NAO observed to have a negative value.  During this same period in time, global temperatures increased.  From the mid 1950's to the late 1970's, was an extended period of negative values of NAO, with only two months in the entire period having a positive value.  During this time in earth's history, many of you probably remember the Great Ohio Blizzard '78 and the snowstorm in March of 1964, where Fort Wayne had their all-time greatest one day snowfall on record of 14.6 inches.  During these years in earth's history, the average global temperature decreased and was actually about 0.8 degrees Celsius cooler than it was today.  From the early 1980's onward to the late 1990's, the earth entered a very warm period, where temperatures the highest ever recorded in the 20th century, in 1998.  In this same period of time, the NAO was in a predominantly positive phase, allowing for above normal warmth to spread farther northward.  Currently we have entered a more stable phase of the NAO, where it has varied from year to year.  In the last two years, scientists believe that we may have entered a negative phase of the NAO, as during the last two years the NAO has been predominantly negative.
The next variable I want to look at is the PNA.  The PNA stands for Pacific North American pattern.  Compared to the NAO and the AO, the PNA does not show any significant trends or cycles in the last one hundred years, and it is a very short term index.  The PNA index refers to the height contour/pressure pattern from the Central Pacific coast to the Pacific Northwest and then towards the Eastern United States.  If the PNA has a negative value, then there is generally a trough and stormy conditions hitting the West Coast, while the Southeast and East Coast enjoy mild conditions, while the Midwest is generally stormy.  When the PNA has a positive value, a ridge is generally present over the West and a major trough is generally present over most of the East.  Over the last several years, and especially during the past 10 months, the PNA has trended towards a positive value, indicating that this trend may continue into the winter months, but to a much lesser extent.  This winter, I expect the NAO to remain negative more so than any of the other values I have been talking about.  While I expect the NAO to continue to be negative, I do not expect  it to be as extreme as last winter.  This winter, the NAO will probably be slightly to moderately negative, indicating that the trough that will develop will be centered more so over the Midwest and Great Lakes, rather than the East Central states.  The AO will more than likely average out to be only slightly negative, also indicating that the trough will be centered more so in the Midwest and Lower Great Lakes than in the East and Southeast.  I expect the positive PNA values to be much less to an extreme, with values closer to zero.  This should allow the trough to be centered more over the Midwest than last year.
     I also used more indices in the development of my winter forecast, especially longer range values such as the PDO.  PDO stands for Pacific Decadal Oscillation, which instead of dealing with pressure surfaces, it deals directly with sea surface temperature anomalies.  Since it deals with temperatures, its value correlates much stronger with the Earth's weather than does the NAO, AO, and the PNA.  According to research climatologists, they have found that the PDO has a distinct thirty year cycle, with which it varies from positive to negative.  Even though the PDO has a thirty year cycle, it can vary from year to year especially in between significant ENSO events.  During a negative PDO period, sea surface temperature anomalies are generally much below normal for the thirty year period for the oceanic region surrounding the Equatorial Pacific, while ocean regions of the Northwest Pacific experience much above normal temperatures.  During a negative PDO period, east and central based La Nina's are more likely to form, especially stronger events, and as discussed above, east and central based La Nina's tend to bring cool temperatures to much of the Eastern United States during the winter months.  Therefore, during the cool or negative phase of the PDO, much below normal temperatures are more likely across the east.  During the warm phase of the PDO, warmer than normal temperatures exist near the equator in the Pacific, while cooler than normal waters exist across the Northern Pacific Ocean.  This type of pattern allows El Nino frequency to increase, while La Nina events can happen and sometimes do happen, they are usually weak and west-based.  Currently, we have just exited the last warm phase of the PDO in the late 1990's, and have entered a cooling phase of the PDO.  As of 2011, PDO values are negative for the first time since the early 1980's.  Over the last year, the PDO has really tanked, signally the start of the next cool phase in the Pacific.  With this cool phase, expect frequent La Ninas, while United States winters get snowier and colder especially across the North.  Also expect an increase in severe weather activity during the next thirty years, especially across the Ohio Valley.  So what does the negative PDO mean for this winter?  Well, I expect that a dropping PDO will cause a strengthening of the La Nina, and going with my forecast of a moderate to strong La Nina at that.  Also, with the last negative PDO regime, (during the 60's and 70's), we saw some of the worst winters on record especially around here, where parts of the Corn Belt and Ohio Valley saw record cold and record snowfall.  During the last year of the negative PDO, Fort Wayne had their snowiest winter on record, with 82.1 inches of snow falling during the winter season of 1981-1982.  So this year,  I would expect much above normal snowfall around here, with frequent bouts of arctic air into our area, as the jet stream will be positioned just to the south of our area.

Decadal averages of PDO values

Solar sunspot activity

   Probably the most significant factor that affects weather here on earth, is the sun.  It really does seem logical that the sun is most important factor in the Earth-Climate system.  Currently, we are in a record low sunspot activity period that hit rock bottom in early 2009.  According to Space Weather scientists, low sunspot activity indicates that incoming solar radiation is at an all time low, which by logic, low solar radiation indicates lower temperatures.  Right now, we are in between Solar cycle 24 and Solar cycle 25, but according to some scientists, solar activity is so low that solar cycle 25 may not even occur, which would contribute to decreasing temperatures here on Earth.  But you may asking, "then why was the past two summers so hot?"  Nobody really can answer this, but it may be due to changes in the atmospheric circulation caused by the record low sunspot activity.  Changes in the atmospheric circulation may also be linked to an increase in greenhouse gasses, or the cool phase of the PDO, but nobody really knows why we had the hot summers.  Even though solar activity has been on the rise, according to the Space Weather Prediction Center, this solar cycle should peak in May of 2013, but in the short term, for this winter, solar activity should drop once more, before rising again in Spring 2012.  Usually, low solar activity during the winter months indicates below normal temperatures across most of the Northern Hemisphere, excluding the arctic regions, where temperatures are usually above normal.  A factor that may affect the cold temperature forecast, is the fact that solar activity has been increasing and may cause a stormier winter over North America than was originally forecast.  One interesting fact that could mean a severe winter for a large part of the United States, is the fact that severe winters tend to repeat in a 34-37 year cycle.    According to an article from Storm Central, this winter may be the winter that brings extreme weather to large parts of the Northern Hemisphere.  According to many meteorologists' predictions, this winter may be the winter that sees extreme storm systems and extreme cold over the Northern and Eastern United States, while Europe will also see violent weather.  This winter could even be the repeat of the winters of 1977-78 and 1978-79 over the United States.  Here is the link to the article: Severe winter article
      With all of these factors in play, this may be the winter to buy a snow blower or new shovel especially if you live in the Ohio Valley, Great Lakes, and Northern Plains, as an extreme winter is forecast with heavy snowfall and colder than normal temperatures.  In my next post, I will give month by month forecasts for the entire United States, based on these trends and indices

Fair weather for Today and Tomorrow... but a big change is on the way!

Right now, as you can all see, it is very nice out, after a very wet and stormy morning, as temperatures have risen into the lower 60's for most areas, and sunny skies have persisted.  By tonight, I'm expecting that skies will remain clear as the the upper level shortwave has cleared the area, allowing for high pressure to build in.  Tonight, temperatures should drop into the upper 30's, but if you believe the computer models, they are keeping the low temperatures in the lower to middle 40's, which may be too high, as I don't think that warm air advection will occur as soon as the GFS model.  By tomorrow, due to quite a bit of warm air advection, I believe that temperatures will rise into the lower 70's, under partly to mostly sunny skies, making for a very comfortable day.  According to the computer models, the clouds and rain shouldn't arrive until later tomorrow evening, when showers and thunderstorms will arrive probably after 9 p.m.  These showers and thunderstorms will continue through the early morning hours and possibly into the morning rush hour.  After this I expect only showers to persist as the low pressure system moves well south of the area bringing with it the band of showers and thunderstorms.  On Wednesday, I expect only scattered showers with highs in the upper 50's.  At this time, this forecast may change quite drastically, as the rain may hold on longer than I am expecting.  By Thursday, temperatures will have dropped into the upper 40's, with showers and chilly conditions.  This will be the day to wear a heavy jacket, as it will feel like November.  Overnight, Thursday, temperatures will drop probably below freezing as a cold air mass takes its place in the Eastern and Central United States.  With this storm system, temperatures will probably drop to the coldest of the entire season.  According to some computer forecast models, a snowstorm may be in the forecast for our area by the end of this week and into the weekend.  This is a long way off, but it is still a possibility.  Stay tuned for forecast updates.

Wild storm forecast this week. Heavy rain, high winds, and even snow!

According to computer forecast models, a large storm may develop as a low in the southern plains moves northeastward bringing with it heavy rain.  This storm system will initially weaken, as indicating by the GFS model, as it moves northeast into southern Ohio, bringing rain and breezy conditions to the area.  After that the model forecasts that a rather intense low pressure system will develop just off the east coast of North Carolina, while a secondary low develops in Kentucky and moves due northward.  The secondary low is the one that will concern us, as the East Coast low will likely remain at an intensity of 992 millibars or weaken as it heads up the East Coast.  The secondary low over Kentucky will likely move due northward, right into Central Ohio.  As it moves northward, the GFS model predicts that the low will deepen to about 981 millibars while it is over Sandusky, Ohio.  During this time period, I believe that we will have heavy rain, which could eventually accumulate to 2-3 inches by Thursday evening when the rain is expected to end.  As the low deepens, I also expect wind speeds to increase rapidly, especially Wednesday into Thursday.  I believe sustained winds may be as high as 35 or 40 mph, with gusts as high as 50 mph, but there is much uncertainty in this forecast.  During the night Wednesday, there is the possibility that the rain changes over to moderate to heavy wet snow for short period of time, possibility accumulating in some areas, but this is pretty unlikely as the air mass will likely be too warm for any snow.  But, if the low pressure system and the rain sticks around for longer than previously thought, there could be a period of time where it snows on Thursday night, as temperatures will likely approach freezing.  Even without the snow, prepare for an exciting week as heavy rain and high winds will likely disrupt your plans.

Snow is a possibility this Week! Official Forecast through Thursday.

For all you snow lovers out there, this may be exciting for you.  This week, some computer models are indicating that snow showers may fall in the lower Great Lakes and Ohio Valley on the back edge of a storm system expected to form in the Ohio Valley on Tuesday, and expected to move into the East.  According to these models, these snow showers may form as a very cold air mass descends out of Canada, which may not allow high temperatures on some days this week to make it out of the 40's, especially on Wednesday and Thursday.  Right now, 850 millibar temperatures forecasts support some back edge snow showers from any left over rain showers, but surface temperatures may not support this possibility as highs will be around 50 in most areas.  The best chance for a snow shower or two would be probably Tuesday or Wednesday Night, as temperatures get pretty close to freezing.  If anything, the snow will be mixed in with a rain shower.  So it may not be that exciting, but it may be a precursor to an early winter!  Even without any snow falling, expect cool temperatures for most of this week, with Monday probably being the best day with partly to mostly cloudy skies with highs in the lower 60's.  For the rest of the week, expect highs in the lower to middle 50's, under mostly cloudy skies, with multiple chances of showers.  By the end of the week, temperatures may moderate slightly to the lower 60's, but this will occur as another storm system enters the area.

Official Forecast through Thursday

Sunday Night: Low 39.  Mostly cloudy in the early evening hours, becoming partly to mostly clear after midnight.  Slight chance of showers early, especially in southern areas.  Canadian storm system will begin to move eastward, allowing another storm system to develop in the Ohio and Tennessee Valleys.

Monday: High 61.  Partly cloudy.  Breezy, with winds from the west.  Storm system begins to develop in Ohio Valley.

Monday Night: Low 41.  Partly cloudy at first becoming overcast, with a scattered showers developing after midnight.

Tuesday: High 50. Overcast throughout the day.  Showers early, becoming a widespread, steady rain by afternoon.  Chance of rain 70%.

Wednesday: High 50.  Mostly cloudy to overcast.  Lingering showers and some heavier pockets of rain.  Chance of rain 50%.  Maybe a snowflake or two at night.

Thursday: High 52.  Mostly cloudy.  Some lingering showers, but they should be scattered to isolated in nature.  Chance of rain 30%.

Technical Winter Outlook Discussion Part Two

After listing off my reasons for the winter forecast, I will give a month by month outlook on what will likely happen this winter, including region-by-region forecasts.  In general, wet and below normal temperatures will be persistent across the northern United States, while the South and Southwest will bask in sunshine for large parts of the winter, allowing for the Texas drought to re-expand.  Across the Northeast and Mid-Atlantic states, I expect them to start off with below normal temperatures and frequent snowfall, but by late January and February, I expect a major warming trend, while the storm track remains over the Ohio Valley.  In the Central Plains, I expect that frequent bouts of cold will hit the region, but precipitation and snowfall will be near to slightly above normal.  Now for the details.

(Disclaimer : This forecast is subject to change and it could change drastically.  Do not use this as a guide to the winter, as it may be wrong and you may solely be disappointed.)

November:  I want to start out with the month of November, mainly because I think that unlike last year, this year's winter may start out by mid-November.  November is looking a bit iffy for a forecast, but it looks like below normal temperatures will prevail across a good chunk of the United States, as the NAO goes negative by early to mid November.  Many regions especially across the North Central Plains will likely see a couple of snowstorms during this time, while other parts of the Great Lakes and Ohio Valley will likely see the start of the Lake-effect season, especially after mid-November.  There may even be some synoptic scale storm systems that bring accumulating snowfall to the Ohio Valley during this time as well.  In the Northeast, this may be the perfect time for a Nor-easter to form, even though it will likely not be a snowstorm.  Across the Southern United States, I expect near to below normal temperatures, along with below normal precipitation, causing the drought to intensify.  Along the west coast, near to above normal precipitation will be the rule, as an active La Nina pattern settles in.  Temperatures will likely be near normal to above normal. 
December: During the month of December, I expect that winter will really set into the U.S., as bouts of arctic air and heavy snow fall across a large part of the East and Midwest.  I expect temperatures to be much below normal (5-7 degrees below normal), from the Northern Plains, southward through the lower Great Lakes.  This region of extremely cold air will cause the predominant storm track to follow the Appalachian mountains and the East Coast, allowing for the formation of a couple of Nor'easters, though not as severe as last year and the year before.  Therefore I expect precipitation to be above normal in the Ohio Valley and lower Great Lakes east of Chicago, towards the East Coast, while snowfall will likely be above normal along the major east coast cities and in the Ohio Valley.  Snowfall will likely be much above normal in the Lake-effect snowbelts.  In the Southeast, temperatures will likely be below normal for this part of the winter, bringing the only chance of freezes for the season.  Precipitation will likely be near normal to above normal which may help drought conditions some.  Across Texas and Oklahoma, there could be some major ice storms along with the cold air, while southern Texas will likely above normal warmth and dry conditions.  In the west, I expect above normal precipitation along the entire coast, and also some parts of the Southwest.  Heavy mountain snows will be frequent as the Pineapple Express sets up shop once again this winter for a time.
January: During January, I expect temperatures to warm quite a bit as a weak southeastern ridge develops across Florida.  This warmth should cause near normal temperatures along the eastern coast, with above normal rainfall and an increase in ice storms, especially in the Mid-Atlantic and lower New England.  In the Ohio Valley and Great Lakes, I expect the cold temperatures to hold on, causing the temperature gradient to increase between the East Coast and areas west of the Appalachians, which should cause a very strong jet stream, and the potential for several blizzards and snowstorms especially from Chicago and Detroit southward towards Indianapolis and Cleveland.  During this time, Lake-effect snow will dwindle especially around Lake Erie, as the lake freezes over quickly.  Across the North Central Plains, very cold conditions will prevail, along with frequent snowfalls from Alberta Clippers.  In the South, conditions should hold dry, with warm temperatures prevailing.  This holds true for Texas and the Southern Plains.  In the Southwest, very dry conditions will be present, as a ridge builds in this region also, along with much above normal temperatures.  Along the west coast, I expect temperatures to be near normal, but with above normal precipitation north of central California.  In the mountainous regions, expect above normal snowfall, as frequent heavy snowfall arrives in the mountains.
February: February should be the most dangerous month, as in heavy snowstorms for the Ohio Valley, Northern Plains, and Great Lakes regions, as I expect one or even two snowstorms to dump 1-2 feet on these regions.  Temperatures during the month of February should cold but could moderate by the end of the month.  Along the East Coast, conditions will probably be slightly drier than normal, as the storm track is displaced farther west from the region, and temperatures also be mild especially in the lower Mid-Atlantic states.  Across the majority of the south, I expect below normal precipitation and above normal temperatures, with the exception of Alabama and Mississippi, who could see a very active start to the severe weather season, especially later in the month.  In the west, I still expect a repeat of La Nina conditions, with frequent heavy rainfall, and frequent heavy mountain snows.  In the northern plains, I still expect a continuation of the cold, but with more snowfall than in previous months.
What this means for Northwest Ohio and Indiana: December: temperatures will be much below normal, with frequent lake-effect snows west of the area, with some lake effect snow affecting our area.  December may seem dry, until a major storm at month's end could bring copious amounts of snow to the area, especially in Northwest Ohio.
January: temperatures moderate some, not as cold as December, but still below normal (2-4 degrees below normal). Clipper systems will be more frequent in the beginning of January, but will transition into major Colorado lows and Gulf lows, that will bring frequent heavy snowfall by the end of January.  Lake-effect snow will likely dwindle, unless Lake Michigan does not freeze over.  Major snowfall amounts.
February: temperatures will continue to moderate as storm track shifts westward slightly.  Once again, I expect major snowstorms to hit the area, with maybe a snowstorm bringing a good 1-2 feet of snow to the region.  Ice storm frequency may increase by months end.  Temperatures will be slightly below normal to near normal especially by month's end.

Technical Discussion of Winter Forecast. Part One

As many of you have probably read my winter forecast, I expect you have a few questions as to why I'm predicting what I am.  In this discussion I will give my major reasons for the forecasts, and a few other almost non-significant reasons as to why I made this forecast.  I am also including month by month outlooks, which will give details on things such as temperature, storm potential, snowfall amounts, and any warm ups.  By mid to late November, I will have a refined forecast, which will explain the month by month setup even more, along with storm track potential and when we can expect our first major winter storm in this region.  For now, let's get on with the discussion.
     The first major factor (and probably the most important of them all), is the fact that yet another La Nina is developing in the equatorial Pacific.  Currently, the Climate Prediction Center has upgraded their La Nina Watch last month to a La Nina Advisory this month in their latest ENSO outlook.  According to the latest analysis, the CPC (Climate Prediction Center) explains that the current La Nina is not near as strong as it was during September of 2010.  This proves the fact that this year's La Nina will probably not be as strong as last year's.  But over the last few weeks, La Nina conditions have been developing very quickly, with current La Nina conditions at about -1 degrees Celsius, which is way below September's ENSO index, which was only -0.6 degrees Celsius (note, when I refer to negative degrees celsius, I mean below normal and not as an actual temperature.  Actual temperatures in the equatorial Pacific are about 18 degrees Celsius.).  This value of the ENSO index indicates a border-line moderate La Nina.  According to the latest underwater temperature anomalies, there is still a very large region of much below normal water temperatures upwelling to the surface from about 100-200 meters below the surface of the ocean.  Most of these below normal water temperatures are occuring in the eastern and central regions of the Equatorial Pacific.  I will explain the significance of this later in the discussion.  Along with the factors that are promoting La Nina, I expect still declining SST anomalies, allowing for the strengthening of the La Nina.  I would expect the La Nina to level sometime in late January 2012 or early February 2012, at a peak of about -1.4.  In fact, this value may change because according to several of the NCEP's climate forecasting models, values may reach or exceed the ENSO index value of -1.5, with the CFSv2 forecasting a peak of about -2.0.  A value of -2.0 would indicate one of the strongest La Nina's on record.  But I really think the CFS's idea of this low of a value is almost farfetched, as current ENSO index levels are not nearly as strong as in 2010 at the same time, and we leveled off just before we could reach Strong La Nina values.  So, in conclusion, I expect the peak of the La Nina to be at -1.4, which is the exact same as last year.  Now back to talking about what east based and west based La Nina means.  In a west-based La Nina, which hasn't happened in several years, the coolest and most concentrated cool waters are located over the western equatorial Pacific, is almost similar to what happens during an El Nino.  Generally, west-based La Ninas cause a very strong ridge to form during the winter months over the East.  This causes much above normal temperatures to extend back into the Plains states, who would normally bring significantly cool temperatures to the plains.  During west-based La Nina winters, the Ohio Valley and Great Lakes would see plenty of precipitation, but not much in the way of snow.  They also tend to reduce Lake effect snowfall amounts.  During east-based La Ninas, widespread below normal temperatures occur over much of the U.S., excluding the Southeast and Florida.  Precipitation is also above normal from the Great Lakes and Ohio Valley on toward the East Coast.  Here are some maps to illustrate what I just explained.

z

Therefore, since this winter's La Nina is east-based I believe that temperatures over most of the Northern United States will be below normal throughout most of the winter.  But making a forecast just based on one variable won't do you any good.  So I went ahead and did research on the NAO.  As I have explained in past articles, the NAO stands for the North Atlantic Oscillation, which indicates that it has to do with the wind patterns across the North Atlantic.  How the Climate Prediction Center determines the daily NAO is by taking the 500 millibar height difference between the Azores and Iceland and comparing it to normal.  If the 500 millibar height difference is large compared to normal, the NAO is considered to be positive.  During positive phases of the NAO, the storm tracks shifts northward, because there is such a large difference in air pressure, the jet stream is very strong, allowing for many storm systems to form over Iceland and make their way into northern Europe.  Generally, winters and summers with a dominate positive NAO will cause much stormier than normal conditions over most Europe in both seasons.  A negative NAO, indicates that the 500 millibar geopotential height difference is smaller than average and the difference can sometimes be negative in some extreme situations.  This situation allows the jet stream to take a more southerly route across the United States and a southerly route toward Europe.  In these situations, the jet stream is weaker across the Atlantic, and causes extended cold, dry periods across all of Europe, and across the United States, the weather tends to be much colder than normal, and it causes a very snowy, stormy weather pattern across the Eastern U.S.  According to trends in recent months, and over the last several years, I expect the NAO to continue a downward trend and become more predominantly negative during the winter months, allowing for below normal temperatures and above normal snowfall throughout much of the east.  Scientists have also studied another index that strongly correlates to the NAO.  This index is the AO.  The AO stands for the Arctic Oscillation, and refers to the wind patterns and temperatures in the stratosphere over the Arctic regions.  When the AO is positive, this indicates that stratospheric temperatures over most of the arctic region are much below normal.  Much below normal temperatures over the Arctic create strong westerly winds in the Arctic stratosphere due to the large temperature difference between the poles and the equator.  With a positive AO, atmospheric blocking in lower layers of the atmosphere is reduced, allowing for an extremely amplified pattern with a strong jet stream over the Atlantic.  When the AO is negative, stratospheric temperatures over the Arctic are much above normal, causing above normal heights and weak easterly winds.  These weak easterly winds cause a ridge of high pressure to form in lower layers of the atmosphere.  This ridge of high pressure generally located over Greenland, will cause a road block in the normal westward wind flow.  The jet stream will move so that there is a major trough over the east, and when both the NAO and the AO are negative, this can create the potential for major storms across the East, especially during the winter season.

In actuality, I have read several articles about research being done on the NAO.  They believe they have found a non-trending multi-decadal oscillation of the NAO.  They have found that the NAO seems to have a thirty year cycle, going from mainly negative values to mainly positive values.  They have found three such periods in the known record, extending back to the 1920's and 30's.  From 1925 on to the 1950's, there was a positive period of the NAO, where only a few times was the NAO observed to have a negative value.  During this same period in time, global temperatures increased.  From the mid 1950's to the late 1970's, was an extended period of negative values of NAO, with only two months in the entire period having a positive value.  During this time in earth's history, many of you probably remember the Great Ohio Blizzard '78 and the snowstorm in March of 1964, where Fort Wayne had their all-time greatest one day snowfall on record of 14.6 inches.  During these years in earth's history, the average global temperature decreased and was actually about 0.8 degrees Celsius cooler than it was today.  From the early 1980's onward to the late 1990's, the earth entered a very warm period, where temperatures the highest ever recorded in the 20th century, in 1998.  In this same period of time, the NAO was in a predominantly positive phase, allowing for above normal warmth to spread farther northward.  Currently we have entered a more stable phase of the NAO, where it has varied from year to year.  In the last two years, scientists believe that we may have entered a negative phase of the NAO, as during the last two years the NAO has been predominantly negative. 
The next variable I want to look at is the PNA.  The PNA stands for Pacific North American pattern.  Compared to the NAO and the AO, the PNA does not show any significant trends or cycles in the last one hundred years, and it is a very short term index.  The PNA index refers to the height contour/pressure pattern from the Central Pacific coast to the Pacific Northwest and then towards the Eastern United States.  If the PNA has a negative value, then there is generally a trough and stormy conditions hitting the West Coast, while the Southeast and East Coast enjoy mild conditions, while the Midwest is generally stormy.  When the PNA has a positive value, a ridge is generally present over the West and a major trough is generally present over most of the East.  Over the last several years, and especially during the past 10 months, the PNA has trended towards a positive value, indicating that this trend may continue into the winter months, but to a much lesser extent.  This winter, I expect the NAO to remain negative more so than any of the other values I have been talking about.  While I expect the NAO to continue to be negative, I do not expect  it to be as extreme as last winter.  This winter, the NAO will probably be slightly to moderately negative, indicating that the trough that will develop will be centered more so over the Midwest and Great Lakes, rather than the East Central states.  The AO will more than likely average out to be only slightly negative, also indicating that the trough will be centered more so in the Midwest and Lower Great Lakes than in the East and Southeast.  I expect the positive PNA values to be much less to an extreme, with values closer to zero.  This should allow the trough to be centered more over the Midwest than last year.
     I also used more indices in the development of my winter forecast, especially longer range values such as the PDO.  PDO stands for Pacific Decadal Oscillation, which instead of dealing with pressure surfaces, it deals directly with sea surface temperature anomalies.  Since it deals with temperatures, its value correlates much stronger with the Earth's weather than does the NAO, AO, and the PNA.  According to research climatologists, they have found that the PDO has a distinct thirty year cycle, with which it varies from positive to negative.  Even though the PDO has a thirty year cycle, it can vary from year to year especially in between significant ENSO events.  During a negative PDO period, sea surface temperature anomalies are generally much below normal for the thirty year period for the oceanic region surrounding the Equatorial Pacific, while ocean regions of the Northwest Pacific experience much above normal temperatures.  During a negative PDO period, east and central based La Nina's are more likely to form, especially stronger events, and as discussed above, east and central based La Nina's tend to bring cool temperatures to much of the Eastern United States during the winter months.  Therefore, during the cool or negative phase of the PDO, much below normal temperatures are more likely across the east.  During the warm phase of the PDO, warmer than normal temperatures exist near the equator in the Pacific, while cooler than normal waters exist across the Northern Pacific Ocean.  This type of pattern allows El Nino frequency to increase, while La Nina events can happen and sometimes do happen, they are usually weak and west-based.  Currently, we have just exited the last warm phase of the PDO in the late 1990's, and have entered a cooling phase of the PDO.  As of 2011, PDO values are negative for the first time since the early 1980's.  Over the last year, the PDO has really tanked, signally the start of the next cool phase in the Pacific.  With this cool phase, expect frequent La Ninas, while United States winters get snowier and colder especially across the North.  Also expect an increase in severe weather activity during the next thirty years, especially across the Ohio Valley.  So what does the negative PDO mean for this winter?  Well, I expect that a dropping PDO will cause a strengthening of the La Nina, and going with my forecast of a moderate to strong La Nina at that.  Also, with the last negative PDO regime, (during the 60's and 70's), we saw some of the worst winters on record especially around here, where parts of the Corn Belt and Ohio Valley saw record cold and record snowfall.  During the last year of the negative PDO, Fort Wayne had their snowiest winter on record, with 82.1 inches of snow falling during the winter season of 1981-1982.  So this year,  I would expect much above normal snowfall around here, with frequent bouts of arctic air into our area, as the jet stream will be positioned just to the south of our area. 

Decadal averages of PDO values

Solar sunspot activity

   Probably the most significant factor that affects weather here on earth, is the sun.  It really does seem logical that the sun is most important factor in the Earth-Climate system.  Currently, we are in a record low sunspot activity period that hit rock bottom in early 2009.  According to Space Weather scientists, low sunspot activity indicates that incoming solar radiation is at an all time low, which by logic, low solar radiation indicates lower temperatures.  Right now, we are in between Solar cycle 24 and Solar cycle 25, but according to some scientists, solar activity is so low that solar cycle 25 may not even occur, which would contribute to decreasing temperatures here on Earth.  But you may asking, "then why was the past two summers so hot?"  Nobody really can answer this, but it may be due to changes in the atmospheric circulation caused by the record low sunspot activity.  Changes in the atmospheric circulation may also be linked to an increase in greenhouse gasses, or the cool phase of the PDO, but nobody really knows why we had the hot summers.  Even though solar activity has been on the rise, according to the Space Weather Prediction Center, this solar cycle should peak in May of 2013, but in the short term, for this winter, solar activity should drop once more, before rising again in Spring 2012.  Usually, low solar activity during the winter months indicates below normal temperatures across most of the Northern Hemisphere, excluding the arctic regions, where temperatures are usually above normal.  A factor that may affect the cold temperature forecast, is the fact that solar activity has been increasing and may cause a stormier winter over North America than was originally forecast.  One interesting fact that could mean a severe winter for a large part of the United States, is the fact that severe winters tend to repeat in a 34-37 year cycle.    According to an article from Storm Central, this winter may be the winter that brings extreme weather to large parts of the Northern Hemisphere.  According to many meteorologists' predictions, this winter may be the winter that sees extreme storm systems and extreme cold over the Northern and Eastern United States, while Europe will also see violent weather.  This winter could even be the repeat of the winters of 1977-78 and 1978-79 over the United States.  Here is the link to the article: Severe winter article
      With all of these factors in play, this may be the winter to buy a snow blower or new shovel especially if you live in the Ohio Valley, Great Lakes, and Northern Plains, as an extreme winter is forecast with heavy snowfall and colder than normal temperatures.  In my next post, I will give month by month forecasts for the entire United States, based on these trends and indices

Second Official Winter Forecast for the Winter of 2011-2012

Finally, after about of a month of research since my last winter forecast, I have finally compiled enough information to create another one.  Just this last week, Accuweather's Long-range forecasting team came out with their first official forecast for the 2011-2012 winter season.  They have provided a forecast for the entire United States calling for another extreme winter season.  Despite the threat for an extreme winter season, they believe the East Coast will be spared this year, with only a few minor threats for snowstorms to the East Coast at the end of December, while the threat for ice storms in the Mid-Atlantic and Northeast will continue into February.  They believe that the drought in the Southern United States to continue, spreading out of Texas, and into the Southeast and Florida, while also spreading westward into Arizona, New Mexico, and Southern California.  In these regions, the Long-range forecasting team at Accuweather expects dry, and relatively tranquil weather for most of the winter season, with maybe a period of time in December where Southern California gets hit by heavy rain and flooding.  For the rest of the south, they expect some relief in the Texas drought, especially along the Gulf Coast, as rain finally returns to Southeast Texas.  For the most part the drought will get worse, especially as we get into next spring, when even drier conditions return to Texas.  Even along the Pacific Northwest Coast, they expect normal La Nina conditions to settle in with, with much above normal rainfall, below normal temperatures and heavy snowfall in the Cascades and Rockies.  But according to the Long-range forecast team, the worst of the winter storms will hit the Midwest, Ohio and Tennessee Valleys, and the Great Lakes.  They expect much above normal precipitation, along with below normal temperatures.  They expect many arctic outbreaks in the middle of the country.  Not only will we have plenty of cold to deal with, but plenty of snow as well, with several major blizzards expected to hit the Ohio Valley, Great Lakes, and Upper Midwest.  Many cities in these regions may receive record snowfall amounts as huge snowstorms are anticipated to impact  many areas.  I will explain later in the article, when and potentially where most of these snowstorms will hit.  In my opinion, with all of the climatic signs lining up just right, I think that they may be pretty accurate with what occurs this winter.
     In this forecast, I do not want to get very technical, so I will get straight to the point in each region.   I will make a forecast for each of six regions, with month by month details on my blog.  These regions are as follows: Northeast (including the Mid-Atlantic states), the Southern U.S., the Southwest, the West Coast (Pacific Northwest), the Rockies and Upper Midwest, and the Great Lakes/Midwest/Ohio Valley region.  I will begin with the Pacific Northwest and West Coast.  As is typical with a La Nina winter, I expect quite a bit of winter precipitation in the Pacific Northwest, including Washington state, Oregon, Idaho, and parts of Montana.  In actuality, the train of storm systems that normally comes with a La Nina winter has already begun in the Pacific Northwest, as the ridge has finally left the west, allowing for a major trough to bring in multiple rounds of storm systems to the West.  In the mountainous regions, I expect a very long and successful skiing season, as snowfall amounts will be extreme in the Cascades, the Sierra Nevadas in California, and for most of the Rockies north of Colorado.  With all of this precipitation, comes below normal temperatures to most of Washington state and Oregon, with regions south of these states, having near normal temperatures for most of the winter.  In the Southwest deserts, I expect for the most part dry and relatively mild conditions for the winter.  This will allow for the drought to re-expand westward from Texas, and raise water concerns for the second winter in a row.  Even with overall drier than normal conditions for the season, during December, as mentioned above there could be period where the Pineapple Express re-opens.  The Pineapple Express refers to a theoretical atmospheric river of moisture that runs northward every once and a while into the West Coast of the United States.  This "atmospheric river" brings very heavy rainfall for days and even weeks on end to Southern California and Arizona.  I expect this to open up at least once this winter as it did last winter.  In the Southern United States from Texas on over to Georgia and Florida, I expect almost the same thing as I do for the Southwest, with much drier than normal conditions and very mild conditions, especially later in the season towards mid-January through the spring months.  Because of La Nina, I would also expect an early and active severe and tornado season throughout February and March, which could impact the same areas that were hit hard last year.  Even though the south seems like it could be devoid of winter weather, don't let your guard down, because there could a few storms that will bring some extreme icing situations to areas such as Oklahoma and Arkansas eastward towards Tennessee, northern Alabama and Georgia, and western parts of the Carolinas.  These storms could bring major power outages along with hazardous road conditions for days.  The most probable time for these to happen will be in December and early January.  Also, expect the drought conditions to spread eastward from Texas during the winter months.  For the next region, the Northeast, I only have to say, that this winter will probably bring a much needed break from major snowstorms and blizzards.  I expect near normal temperatures with above normal precipitation.  Though, do not let your guard down, as there may be a significant blizzard and snowstorm that sneaks its way up the East Coast, and bring one of the only major snowfalls of the season to most areas especially south of New York City and Hartford, Connecticut.  Areas north of here may experience more snowstorms and a lot more cold air than coastal southern areas.  After mid-January, due to the development of a stronger Gulf of Mexico ridge, and due to warm onshore air flow, I expect some warming to occur especially in coastal areas, where by February, most of their precipitation will be heavy rains from storm systems.  In the interior northeast, temperatures will likely not warm very much or they may not change at all from the previous cold temperatures as the Appalachian mountains will likely keep the warm Atlantic air mass from moving to much farther westward.  Winter over the interior Northeast will likely be severe, as very cold air moves into the region from the Arctic, and as major storm systems move along the Appalachian mountains, creating many situations where heavy snowfall is possible.  As for the Northern Plains and Rockies, I expect snowy and the coldest conditions of anywhere in the United States.  All winter long, I expect an arctic air mass to remain in place, allowing for temperature departures from normal to be near -5 to -7 degrees below normal.  With the jet stream coming out of Canada from the northwest, I also expect a snowier than normal winter with multiple threats of snow from Alberta Clippers which generally bring strong winds, heavy snowfall and bitter cold.  There may also be one or two Panhandle hooks, which swing into Texas, and then make a sharp turn toward the north and generally bring blizzards to the Northern Plains.  Now, finally, for the worst forecast of them all, the Ohio Valley, Great Lakes, and Midwest regions.  In this region, all of the climatic variables seem to be pointing to a very snowy winter, with very cold conditions throughout most of the winter also.  The predominant storm track will be through Kentucky, Tennessee and West Virginia during most of the winter, meaning that most of the Ohio Valley and Great Lakes will mostly see snow during the winter months.  Because these storms will have access to moisture from the very warm waters of the Gulf of Mexico, allowing for the formation of very heavy snowfall with several storm systems.  This year, we may actually see some classic blizzards over the area that dump over a foot of snow, and not just once but several times, especially in mid January through mid February.  There may also be some Alberta Clippers that bring widespread snowfall amounts of 3-6 inches, but most of these will occur in December.  With the heavy snowfall we could also see some very cold air arrive and stick for most of the winter.  Temperature departures may be as low as six degrees below average for December and January.  There is the possibility of a slight warm-up occurring during the month of February, which could lead to the possibility of an ice storm leading to hazardous roads and power outages.  Along with the cold arctic air, the Lake-effect snow will be substantial once again, as the Great Lakes water temperatures are much above normal and I expect much of this heat to be retained throughout the winter.  This will allow for multiple outbreaks of heavy lake-effect snow, which will cause much above normal snowfall in all lake effect snowbelts right along the Great Lakes.  Northwest Ohio may even see some of this snowfall especially during some of the stronger outbreaks in December!
    Overall, I see an extreme winter for a large portion of the Northern United States, leading to heavy snowfall and very cold air to much of the region.  In many ways I expect this winter to be very similar to last year, expect for the fact that I don't believe the Northeast will have near the amount or strength of winter storms from last year, and I expect the heaviest snowfall to fall in the lower Great Lakes region, a belt from Chicago and Detroit on down to Indianapolis and on over to Cleveland.  If I were you, I would prepare now for a very dangerous winter.  Even though the forecast could change dramatically over the next month, and we could end up having very little snow.  But, right now, this is the most likely to happen, given how the climatic signs and forecasts are lined up.

Official Forecast through Thursday

Sunday Night: Low 53.  Partly to mostly cloudy. Light winds from the southeast.  Ridge begins to move out of the area.
Monday: High 80. Partly cloudy.  Ridge still in place, as trough over the west moves into the Rockies, causing periods of severe weather over the plains.  Winds from the south.  Ridge begins to move out of the area and break as large trough makes its way into the Plains.
Monday Night: Low 54.  Partly cloudy. Clouds begin to increase overnight, as storm system in the plains strengthens.
Tuesday: High 77.  Clouds increasing throughout the day, becoming partly to mostly cloudy.  Storm system approaching from the plains, bringing the chance of rain by late evening and the overnight hours.
Tuesday Night: Low 53. Mostly cloudy.  Very low chance of showers in the overnight hours.  Storm system over the plains will intensify.
Wednesday: High 74. Mostly cloudy to overcast. Slight chance of showers in the afternoon.  Plains storm system continues to move northeast.
Thursday: High 66. Overcast will showers and possibly a thunderstorm likely.  Rain will likely be widespread as storm system moves into the area.  Winds become stronger.



Winter outlook: My winter outlook will be issued later this week, as I have been evaluating the climatic signs for winter.  With what I have seen so far, this may be one of our worst winters in years, with heavy snowfall and severe cold.  Stay tuned.

Official Forecast through Tuesday.

Right now, light to moderate winds and clear skies have allowed for very warm temperatures over most areas.  Most areas have risen into the lower 80's, with a few locations in the upper 70's.  Expect temperatures to drop quickly outside especially during the football games, so keep a jacket especially since temperatures will be in the low to mid 60's by 10 p.m.  Overnight, light winds and low dew points in the lower 50's, will allow temperatures to drop rapidly into the lower 50's.  Over the next several days, through next Tuesday, expect much of the same weather, with clear skies, light winds, and warm temperatures
Friday Night: Low 52. Mostly clear with light southwesterly winds bringing in a very comfortable warm air mass.
Saturday: High 82-84 (isolated areas may hit 84 or 85).  Very warm and comfortable day, as skies are still sunny to mostly sunny and warm southerly winds bring in a warm air mass.
Saturday Night: Low 55. Mostly Clear  Ridge is still in place over the area, but it shifts so that there are southerly winds in all levels of the atmosphere.  Trough in the west brings very stormy conditions to the West.
Sunday: High 81. Mostly sunny.  Very large and amplified ridge still in place.  Trough in west amplifies, causing an amplification of the ridge over our area.  Temperatures increase along with southerly winds.
Sunday Night: Low 55.  Mostly clear. Light winds from the southwest.  Ridge begins to move out of the area.
Monday: High 80. Partly cloudy.  Ridge still in place, as trough over the west moves into the Rockies, causing periods of severe weather over the plains.  Winds from the south.  Ridge begins to move out of the area and break as large trough makes its way into the Plains.
Monday Night: Low 54.  Partly cloudy. Clouds begin to increase overnight, as storm system in the plains strengthens.
Tuesday: High 77.  Clouds increasing throughout the day, becoming partly to mostly cloudy.  Storm system approaching from the plains, bringing the chance of rain by late evening and the overnight hours.

Official Forecast through Monday

Official Forecast

Wednesday Night: Low 49. Mostly clear, with surface high pressure causing westerly winds.  Upper level ridge continues to move eastward, causing warmer temperatures to move in.

Thursday: High 81. Mostly sunny, a ridge over the area keeps our temperatures above normal and skies clear.  Light winds from from the south. 

Thursday Night: Low 52.  Mostly clear.  Light southerly winds.  Ridge is still over the area keeping warm temperatures in place.

Friday: High 81. Mostly sunny, again, with warm southerly winds in place.  Ridge still in place over the area, blocking storm systems into Canada and allowing for sunny conditions once again.
 Friday Night: Low 53. Mostly clear with light southwesterly winds bringing in a very comfortable warm air mass.
Saturday: High 82-84 (isolated areas may hit 84 or 85).  Very warm and comfortable day, as skies are still sunny to mostly sunny and warm southerly winds bring in a warm air mass.
Saturday Night: Low 55. Mostly Clear  Ridge is still in place over the area, but it shifts so that there are southerly winds in all levels of the atmosphere.  Trough in the west brings very stormy conditions to the West.
Sunday: High 83. Mostly sunny.  Very large and amplified ridge still in place.  Trough in west amplifies, causing an amplification of the ridge over our area.  Temperatures increase along with southerly winds.
Monday: High 82. Mostly sunny.  Ridge still in place, as trough over the west moves into the Rockies, causing periods of severe weather over the plains.  Winds from the south.
Long range forecast: Right now, its looking like the ridge will stay in place over the area through next week, as a trough attempts to push it out of the area. It is unclear what will happen right now, as computer models yesterday said the ridge would stay in place and today the models are showing that a major trough will develop in the area for a few days.  This type of trough is different from the cut-off low from last week.  This trough will be very progressive, meaning it will produce some pretty big storm systems but it will move out of the area quickly.  After this, another trough is expected to build in the west, allowing a reamplification of the ridge with warmer than normal temperatures prevailing.

Official Forecast through Sunday.

Tuesday Night: Low 47.  Partly cloudy in the evening, with clouds clearing up as upper level low moves off the east coast. 
Wednesday: High 77. Mostly sunny, with a few clouds from time to time. Upper level ridge beginning to move over the area, allowing much warmer temperatures. 
Wednesday Night: Low 49. Mostly clear, with surface high pressure causing warm southerly winds.  Upper level ridge continues to move eastward, causing warmer temperatures to move in.

Thursday: High 78. Mostly sunny, a ridge over the area keeps our temperatures above normal and skies clear.  Light winds from from the south-southeast. 

Thursday Night: Low 52.  Mostly clear.  Light southerly winds.  Ridge is still over the area keeping warm temperatures in place.

Friday: High 80. Mostly sunny, again, with warm southerly winds in place.  Ridge still in place over the area, blocking storm systems into Canada and allowing for sunny conditions once again.
 Friday Night: Low 53. Mostly clear with light southwesterly winds bringing in a very comfortable warm air mass.
Saturday: High 80.  Very warm and comfortable day, as skies are still sunny to mostly sunny and warm southerly winds bring in a warm air mass.
Saturday Night: Low 55.  Ridge is still in place over the area, but it shifts so that there are southerly winds in all levels of the atmosphere.  Trough approaches the Central Plains.

Snowfall records at Fort Wayne. Comparison of Last Winter to other Winters

As all of you probably, the winter of 2010-2011 was a very snowy season here in Northwest Ohio and Northeast Indiana.  At one point in the winter you might've actually thought that we must be breaking snowfall records.  Well, I'm here to tell you that you were right.  According to the National Weather Service's last publication of snowfall for each year since 1943, with seasonal and July through June snowfall records back to 1941, the year 2011 has had 35.7 inches of snow, which is actually right near the average of 35.1 inches.  The reason for this is because in March, Fort Wayne is expected to receive approximately 6.3 inches of snow, but this March we had only 1.2 inches and that occurred right after a storm system brought heavy rainfall to the area on March 6.  In April, we didn't even see a trace of snow, which further brought snowfall totals down for the year.  Even though it seemed like a snowy winter, in reality the snowfall for this year is only just above normal.  It is likely though, according to what long-range meteorologists are predicting for December, we could have quite a bit of snow during the month, closer to 15 inches, which is much above the normal of 7.4 inches for December.  This will probably lead snow totals for this year to near 50 inches which we haven't seen in at least 15 years.  If you look at the snow totals another way such as total snowfall from July of one year to June of the next year.  This way you can get accurate snowfall totals for the entire winter season.  This July through June period we had an amazing 46.5 inches of snow, which the last time we had this much snow it was in 2002, and even then they had 46.7 inches of snow.  Before that, it has been since 1983-84 that we have seen this much snow, with 49.1 inches of snow falling throughout the season.  Another measure of snowfall is the winter total snowfall, where the months that snowfall is logged in is December, January, and February, the core winter months.  Last winter season, Fort Wayne logged 45.3 inches of snow, which means that most of last winter's snow fell during the core winter months.  What this means with global warming will be discussed in later article, but I will tell you this that if nearly 98% of our yearly snowfall is falling in only three months, that means that 9 out of the 12 months of the year here at Fort Wayne are getting warmer, but the core winter months are getting colder.  Anyway, back to the point, this 45.3 inches snow that fell during the winter months was the third greatest snowfall during these three months in Fort Wayne's history, behind the winter of 1977-1978 (49.3 inches) and the winter of 1981-1982 (61.2 inches).  According to my forecast, and many other meteorologists' forecasts, I believe that next winter, we may have even more snowfall than last winter, especially in the months of January and February.  According to some meteorologists, we may have some blockbuster storms this winter which could be much like the 2011 Groundhog Day Blizzard, not just one of them, but two or even three of them.  This winter could be even worse than last winter, which would be almost unimaginable.
If you want to know more about snowfall during past winters at Fort Wayne, visit this link: Snowfall Fall records at Fort Wayne; and then click on "Fort Wayne snowfall records" and you will find a PDF document that tells you past snowfall information.

Official Forecast through Saturday.

Monday Night: Low 44.  Mostly clear at first, but high clouds increasing somewhat overnight, due to proximity of upper level low over the East Coast. No precipitation expected. Northwest winds, becoming more northerly at 5 mph.  Very nice and comfortable night.
Tuesday: High 73. Partly cloudy for the most of the day.  Upper level low begins to move off the East Coast, allowing for height rises and warmer temperatures.  Winds from the north at 10 mph. Very comfortable, warm day to be outside.
Tuesday Night: Low 52.  Partly cloudy in the evening, with clouds clearing up as upper level low moves off the east coast. 
Wednesday: High 75. Mostly sunny, with a few clouds from time to time. Upper level ridge beginning to move over the area, allowing much warmer temperatures. 
Wednesday Night: Low 53. Mostly clear, with surface high pressure causing warm southerly winds.  Upper level ridge continues to move eastward, causing warmer temperatures to move in.

Thursday: High 77. Mostly sunny, a ridge over the area keeps our temperatures above normal and skies clear.  Light winds from from the south-southeast. 

Thursday Night: Low 52.  Mostly clear.  Light southerly winds.  Ridge is still over the area keeping warm temperatures in place.

Friday: High 78. Mostly sunny, again, with warm southerly winds in place.  Ridge still in place over the area, blocking storm systems into Canada and allowing for sunny conditions once again.
 Friday Night: Low 55. Mostly clear with light southwesterly winds bringing in a very comfortable warm air mass.
Saturday: High 80.  Very warm and comfortable day, as skies are still sunny to mostly sunny and warm southerly winds bring in a warm air mass.