Record Breaking Warmth Overspreading the Nation.

As I have said over the last several days, the wave of warmth overspreading the nation will be record-breaking in many aspects.  Even in our local area it will be unprecedented.  Temperatures will approach record highs for several days this week, and even well into next week.  For example, tomorrow, it is possible that temperatures reach the upper 70's and lower 80's in some areas (depending on how cold it gets tonight, especially if a weak frontal boundary sags farther south than what is expected).  This high is calculated based on using 850 millibar temperatures.  The idea behind it is that during a regular spring or summer day, the wind and solar heating will cause the entire boundary layer (the first several thousand feet from the surface) to mix out, allowing warm air aloft to mix to the surface.  I will show you how I did my math.  If you assume that the warm aloft is brought to surface by the Dry Adiabatic Lapse Rate (the rate at which the temperature of air changes as it is moved up or down.  On Earth, this lapse rate is approximately 10 degrees Celsius/kilometer), and if you can determine how far above the earth the 850 millibar layer is, you can find the surface temperature for that day.  Assuming that the 850 millibar temperature is 12 degrees Celsius and its height was 1530 meters (which is the conditions that will be existent tomorrow across the area), then you would add 15.3 degrees Celsius to 12 degrees ( first divide 1530 by 1000 , multiply that by 10 to get 15.3), yielding a high of 27.3 degrees Celsius or 81 degrees Fahrenheit.  You would not be able to use that number alone because we are above sea level by 200 meters or 720 feet, which would cause the actual high to be a couple of degrees cooler.  Since we are not that far above sea level, it will not make much a difference, considering the fact that even warmer air aloft could be transported to the surface, making this high temperature forecast true.  So after a high somewhere in the upper 70's on Wednesday, expect the development of scattered thunderstorms after midnight in northern areas, mainly in Michigan.  These storms will eventually develop southward, bringing the thunderstorm potential to most of the area by Thursday morning and afternoon.  This type of pattern will continue into Saturday, before large scale height rises in the upper atmosphere, cause an enormous ridge to develop that extends as far north as the Hudson Bay.  This will lead to a widespread surge of tropical moisture and warmth into the area, including temperatures into the upper 70's and lower 80's next week, along with very moist air.  Even most of the severe weather by the middle of next week will be concentrated in Oklahoma and Kansas, by the end of next week, severe weather may move into our area as a potent storm system affects the region.  Enjoy this warmth while it lasts, as this event is very rare and only happens every decade or so.

Important Update

I have been monitoring the latest trends in the storm system, and it looks like the severe threat could extend farther south than what was indicated this morning.  Upper level forcing is expected to move over the area in a few hours, causing the development of strong thunderstorms to our northwest over southwest lower Michigan and Northwest Indiana.  This thunderstorms will more than likely only sideswipe most areas that are south of Route 6, with a much more robust severe weather threat north of Route 6.  The main threats will be damaging winds and large hail, but tornadoes are also beginning to look like a possibility especially just north of the Michigan border.  Instability is on the increase west of us, and should soon develop in our area, as the area of clearing moves in.  Temperatures have warmed very nicely despite cloud cover.  As soon as clouds move out, I expect temperatures to jump several degrees, possibly just shy of 70.  Tonight, thunderstorms will impact the area after about 7 or 8 p.m.  These thunderstorms could be severe, but mainly north of Route 6.  Tomorrow will be a very nice day with temperatures in the upper 60's and lower 70's as upper level ridging builds into the region.  Light winds and a dry air mass will promote intense cooling Tuesday night, with temperatures falling into the mid 40's, instead of the mid 50's.  Despite this, temperatures on Wednesday will soar to near record levels, with most regions in the area hitting the middle 70's, under sunny skies.  By Wednesday Night, a stalling frontal boundary will approach the region, causing the development of scattered thunderstorms.  These storms probably will not be severe, but they could cause locally heavy rainfall in some areas, due to the highly moist air mass expected to arrive in the area.  Thursday, Friday, Saturday, upper level ridging will only get stronger, even with a series of shortwaves moving around it.  These individual shortwaves will initiate thunderstorms along the frontal boundary in Michigan, which will be a continual threat through Saturday.  These storms could also bring locally heavy rainfall.  At the same time, the rather moist and warm air mass will still remain across the area, keeping temperatures in the lower 70's and nighttime lows above 55.  Just to show how warm this air mass, I will tell you a little fact.  According to the National Weather Service, a nighttime low of 55 or warmer in mid-March has only occurred TWICE in Fort Wayne's 110 years of record keeping.  The forecast for the next week or so is showing at least five days could have lows above 55 degrees (mainly Wednesday, Thursday, Friday, Saturday, and Sunday.).  Next week, the ridge will amplify, causing an even greater surge of tropical air into the region.  In fact, it could get so warm by Monday and Tuesday, some areas could be seeing temperatures as high as 80 degrees!  Many March's in the last 30 years haven't even seen a 70 degree day.  Back in 2008, we were well below average and very snowy.  This  is how extreme the weather pattern has been.  The GFS is showing a quick end to the "heat wave" by the 24th of March, with a potential freeze. It is highly unlikely that this cold wave will last long at the end of March, especially given the current pattern.  Opposite the GFS, the ECMWF model is showing that the ridging will hold, allowing the warmth to continue.  I will continue to monitor this very nice late-spring weather in coming days, as we could see several temperature records broken!

Forecast Updated

The Experimental forecast page has been updated.  Come check it out for a brief long-range forecast and the forecast for this week.

Stormy at First, then Spring

I have good news and some bad news.  For the bad news, current data suggests the potential for thunderstorms tomorrow, mainly south of the Michigan/Indiana border.  If the thunderstorm threat persists longer into the day, then I highly doubt that temperatures will make it much past the lower 60's and upper 50's.  The initial waves of showers look to arrive in late afternoon for areas west of here such as Northern Illinois and possibly even Northwest Indiana, while the initial waves of showers for Indiana and Ohio will not arrive until about 10 p.m. to midnight.  A more solid line of convection will make its way to the Ohio Valley and lower Great Lakes by the early morning hours, with the NAM suggesting these showers and possibly thunderstorms will arrive by 4 or 5 a.m., and the GFS suggesting a much faster solution of arrival around 3 a.m.  Rainfall amounts will likely be near a half inch, with higher amounts of rainfall farther west near Chicago and Illinois.  After the initial warm front passes through the region, temperatures will warm quite nicely from the overnight lows of the mid to upper 40's, into the lower 60's.  If enough diurnal heating takes place tomorrow,  (aka. sunshine) then it is possible that any weak instability that forms do to the heating, will cause the scattered development of thunderstorms, with some taking on severe characteristics, especially with the wind profile that is suggested by the NAM.  This would be supportive of small hail, and a few damaging wind gusts.  Right now, this is only small possibility as the best lifting from the upper level system will have moved out of the region by the time that conditions would be conducive for severe weather.

GFS forecast of the 500 millibar closed low at 5 a.m. tomorrow morning

Conditions will then clear for Monday night, with temperatures dropping into the upper 40's.  Through most of the upcoming week, expect sunny conditions and very warm weather, with highs likely hitting the 70's for several days in a row.  There are some thunderstorm chances coming up, especially Wednesday night into Thursday and next Saturday night, but these rain chances will be rather small, and will not affect temperatures much.  In fact, the latest GFS is forecasting this warmth to last even into the next week, and it really isn't showing much of an end to the warmth even 16 days into the future!  According to the WFO IWX (Northern Indiana's National Weather Service office), they would be not surprised to see the lower 80's by the week after this week, that's how warm this pattern is going to be!  Enjoy!

Nice, Spring Weather Arriving

It may seem not to spring-like right now, with temperatures in the upper 30's and extremely dry air, but a major change is coming once again.  A rather large upper level ridge will anchor itself across the Central and Eastern United States by tomorrow.  Tomorrow, it is expected that southerly winds will bring in a much warmer air mass to the region, with temperatures rising from the mid 20's to the lower and mid 50's by Saturday afternoon.  On Sunday, strong warm air advection with the low levels ahead of a storm system ejecting out of the American Southwest will cause temperatures to jump into the lower and mid 60's, with possibly windy conditions.  By Sunday afternoon, clouds should cause skies to become partly cloudy and by evening mostly cloudy.  Sunday night lows will likely be in the lower 50's, as showers and thunderstorms move through the area, especially after 3 a.m.  Most shower and thunderstorm activity will move out of the area by mid to late morning.   After this, depending on the amount of cloud cover, temperatures should rise into the mid 60's by Monday afternoon.  On Tuesday, clear skies, warm southerly winds and a strong upper level ridge will allow temperatures to jump to near 70.  For the rest of next week, it looks as if temperatures will remain in the upper 60's and lower 70's, even through next weekend.  Stay tuned for further updates.

New Forecast

For anyone who wants a forecast, I have just updated the Experimental Forecast Page.  Right now, I do not have time to write a blog post explaining everything, but the forecast should answer most of your questions.  For a little bit of forecast information; I am becoming a bit concerned for yet another major severe weather outbreak across the Ohio Valley, Tennessee Valley, and even the lower Great Lakes by late this weekend and early next week.  The details are unclear right now, but I will continue to watch the situation.  Another bit of information is that it doesn't look like any major or sustained cold air will make it into the United States for the next several weeks.  If this is true, it might mean that we have just our last shot at winter, with the snow flurries this weekend.  Everybody its time to get out the summer clothes, because spring has just arrived!

Storm Threat Not Over

I am very sorry for not posting about the storm threat today, but I have been very busy.  The main line of storms is beginning to shift out of Northwest Ohio.  Behind this line of thunderstorms, temperatures will rise quickly into the mid and upper 50's, with a few places mainly south of Fort Wayne, reaching into the lower 60's.  This could generate enough instability ahead of the cold front, that a low-topped squall line could develop and race through areas SOUTH of Fort Wayne.  I do not think that any town north or northwest of Fort Wayne will see severe weather, so do not expect it.  Even areas northeast of Fort Wayne will probably have a hard time seeing any kind of strong thunderstorm.  There will be strong lifting and forcing which would replace the need for instability, which is why the Storm Prediction Center has said that the only way that we could get severe weather is if this low-topped squall line forms, which will bring strong, damaging winds and possibly some hail, maybe even a weak tornado.  Other than that, the cold front will pass through near early evening, with lapse rates becoming very high, allowing the transport of momentum of high wind aloft to the surface, combined with the strong surface pressure gradient, which will cause winds higher than 40 knots, which is near 50 mph.  This may mean that our wind advisory could be upgraded to a High Wind Warning, especially if gusts become over 55 mph.  Temperatures will rapidly drop into the lower 30's tonight, with snow showers possibly pivoting into the area with the comma head.  On Sunday, a shortwave will drop through bringing a greater chance for snow showers and much colder temperatures than what we have been seeing.  By next week, another warm up will be on the way, with possibly another heavy rain event/ or severe weather event by Thursday.  I will keep an eye on this over the next couple of days.

Incredibly Warm Day.

After a very cool and foggy start to the day (and after quite a bit of rain over a half an inch), skies have competely cleared and temperatures have soared into the upper 60's in most if not all areas south of Route 6.  Most areas north of Route 6 are still seeing temperatures in the fifties and cities such as Toledo haven't even hit 50 yet today!  Currently in Antwerp, the temperature is steady right near 69 degrees, with Fort Wayne at a very warm 68.  I can tell you this, these temperatures were a lot higher than what I was expecting earlier today.  I actually thought that temperatures may not even hit 60 when I woke up this morning, the warm advection behind the warm front was so incredible and the mixing was so incredible, that temperatures were many degrees warmer than MOS guidance and computer models.  It still does appear that thunderstorms will not form this afternoon, as the dry line is moving through right now, without initiating an convective development.  Even with the weak to moderate surface based instability, thunderstorms still have not had a chance to form.  After the cold front moves through, which will probably happen around 5 or 6 p.m., winds will continue to be strong for a little while longer before subsiding, as the upper level trough pivots through the area.  Most if not all wrap around precipitation will hit north of the area, with some showers around the Michigan.  As for the next couple of days, by Friday, another strong system will be located in the area, with heavy rain and severe weather all possible once again, including very warm temperatures.  I will have more updates tomorrow on this storm.

Forecast Update

It seems as if tomorrow's situation keeps changing every hour, so I will give you the latest consensus among the data.  It looks like the rain will probably start a bit later than what I said yesterday.  Yesterday, I mentioned that precipitation would probably start after 11 p.m., well now, it looks like rain will start around midnight.  In my opinion, I still think that precipitation will begin around the late evening hours, probably around 10 or 11 tonight.  It just all depends on how quickly the storm system moving into the plains occludes, because storm systems tend to accelerate until they occlude, which by that time, they tend to slow down considerably.  This will lead to timing issues with the onset of strong isentropic upglide, upper level forcing, the works... which will all eventually lead to the point at which the atmosphere above is saturated.  As was the trend in models, the storm looks to strengthen and accelerate for the next few hours, then occluding over the Northern Plains somewhere over southern Minnesota.  The storm looks to become fairly strong before becoming vertically stacked (this means that the storm system does not have a tilt to it when moving up from the earth's surface.  In a strengthening storm system, the surface low is located farthest east, while the 500 and 300 millibar lows and troughs, tend to be located north and west of the surface low.  When a low pressure system becomes vertically stacked, all of the upper level storm systems are located directly above the low, causing it to strengthen for a little while longer, but then weaken as it is source of development has been cut off.), which at the time that it is expected to become vertically stacked, the warm sector will be right over the area.  Tonight, no matter what time the rain arrives, it will become steadier and heavier with time, with embedded heavy thunderstorm development after 3 a.m.  By 7 a.m., scattered heavy thunderstorms will still be located in the area, leading to localized heavy rainfall amounts in some parts of the area.  After 9 a.m., most if not all thunderstorm development will cease, with rapidly clearing skies and strong southerly winds bringing in warm, moist air to the region.  Temperatures will soar into the lower and middle 60's across the area, with upper 50's at the Michigan border.  With increasing lapse rates, strong mixing will occur, bringing much higher winds aloft to the surface, increasing wind speeds as high as 40-50 mph.  Strong mixing could also cause the development of showers and thunderstorms in the warm sector ahead of the mesoscale dry line that is expected to pass through the area.  Right now, the highest chance for scattered thunderstorms after 2 p.m. is expected east of I-69, as the axis of highest instability and highest moisture, will move through the areas at the same time that low level convergence will be strongest.  Some models such as the GFS, are indicating that mixing will be so strong that dry air aloft will mix down to the surface, inhibiting significant convective development.  On the otherhand, the NAM has dew points well above what the GFS is forecasting, with dew points near 60, with temperatures near 65.  This would potential lead to thunderstorm development, but the NAM also has a very narrow opportunity for thunderstorm development, dry air mixing to the surface after 4 p.m., so thunderstorms may not ever form tomorrow afternoon, not in our area to the say the least.  My current thinking is that thunderstorms will form if the NAM is correct with the higher dew points in the area, especially if the left exit region of the jet streak ends up right over our area.  These thunderstorms could produce gusty winds and some small hail as they pass quickly through the area.  After they pass, the cold front will quickly pass through the area, with temperatures quickly dropping, but with strong winds continuing throughout the late afternoon.  Some showers and maybe a snow shower may pivot through the area by nightfall, with mostly cloudy skies and falling temperatures.  After this storm passes through, our attention will focus on the next potentially major storm system, which will further impact the area by Friday and Friday night.  Stay tuned for further updates.

A Few Changes

It was very nice day today, with highs approaching the mid 40's under sunny skies.  Winds did get quite strong today, with gusts as high 30 mph.  One of the few things I would like to change to my forecast is tonight's low temperatures.  It seems as if the winds will dying down earlier than what was expected, plus, the cold front currently moving through the area was producing more substantial cold air advection than what I was expecting last night.  So expect lows tonight to drop down to about 23-25 degrees, under clear skies, and relatively light winds.  By tomorrow, clouds will begin to move in from the west, with skies mostly cloudy by late afternoon.  Right now, it does look like precipitation will start a bit later than what was originally forecast.  Instead of around 9 or 10, it now looks around 11 p.m., so only a slight change in when the precipitation will begin.  Areas that are north of Defiance, will likely experience a very brief period of freezing rain before completely changing over to rain.  Do not expect much in the way of ice accretion though, unless you live in southern Michigan, which they might see some ice accumulation.  Throughout most of the night, rain and thunderstorms will prevail, with thunderstorms most likely occurring south of Route 6  There will be a rather large temperature gradient across the area during the morning hours, with temperatures in the low to mid 30's in southern Michigan, and temperatures in the mid and possibly upper 40's near and south of Fort Wayne.  One interesting thing that will happen on Wednesday during the morning and afternoon hours is that the atmosphere will quickly destabilize, with low level temperatures cooling very rapidly with height. With a strong cold front pushing through the area by mid-afternoon, I would expect scattered to widespread thunderstorm development along the cold front, with a few gusty thunderstorms possible also.  Highs now on Wednesday, could get as high as 65 degrees in the area, mainly south of U.S. 24, even though most areas will reach the upper 50's and lower 60's.  The one factor that would really limit a more sustained thunderstorm threat around here, is the fact that the axis of highest moisture could shift off to the east to quick for the cold front to interact with this moisture and produce stronger thunderstorms.  We would also be having more of a low topped supercell threat if large low level helicity values continue in our area, but models are indicating that most of the low level helicity will be moving out of the region before thunderstorm initiation occurs.  IF thunderstorms do form Wednesday afternoon, they will likely organize into a low-topped squall line, capable of producing brief heavy downpours, high winds, and hail.  If no organized thunderstorm threat develops, then expect as the cold front rushes through, for winds to rapidly increase, with winds over 50 mph possible.  By nightfall (and possible late afternoon), a few showers will pivot through the area as the back side of the system moves through the area.  Temperatures will cool into the low to mid 30's, with clearing skies.  By Thursday, temperatures will begin their warming trend once again, with highs back into the mid 40's.  On Friday, it looks as if yet another storm system will be in the making, with showers and thunderstorms possible once again.  According to current forecast soundings for Friday, our thunderstorm threat may be much more mature on Friday, but the limiting factor with Friday's thunderstorm is weak moisture return from the Gulf of Mexico.  This is because of another severe weather outbreak expected in the southern United States, which will limit moist flow northward.

Storm System Later this Week

After reviewing quite a bit of data, this upcoming week looks quite interesting.  I have been looking at the main synoptic models, which have been fairly consistent with their solutions.  For one thing the next couple of days look quite interesting, with strong winds on both Monday and Tuesday.  Tomorrow, a weakening low pressure system will bypass, dragging a cold front along with it through the area.  This will cause temperature lapse rates to steepen quickly, promoting strong mixing of the boundary layer (low levels of the atmosphere).  This will act to transport strong winds aloft to the surface.  Winds will be fairly strong tomorrow, with gusts as high as 35 miles per hour.  Monday afternoon, as the surface cold front drops through, temperatures will drop back into the 30's, and with clear skies Monday night, temperatures will likely drop into the upper 20's, before weak WAA (Warm Air Advection) at the 850 millibar level causes temperatures to rise by Tuesday morning.  On Tuesday, a thickening cloud layer will move into the region by mid afternoon, ahead of the next major storm system.  As the storm system moves closer, winds will become stronger and gusty, but not as strong as they were on Monday.  By Tuesday night, at about 9 or 10 p.m., rain and possibly sleet or freezing rain could begin to fall.  If the mid levels of the atmosphere above us are drier than currently forecast at the onset of precipitation, winter precipitation may be much more of a threat than what model output indicates now.  Right now, I am not too concerned with this, especially because of how strong the warm advection will be Tuesday night.  For right now, there is still the possibility that it could happen.  This will be a situation that I will continue to monitor in coming days.  Rain will continue for most of the night, with several embedded thunderstorms after 3 a.m.  Precipitation will quickly end by 9 a.m. in most locations on Wednesday, with areas north of Route 6, still seeing showers for a little while longer.  Due to the strength of this storm system, a strong temperature gradient will set up across the area from near the Michigan/Indiana state line to Lake Erie.  This will mean temperatures near and over 60 in Fort Wayne and areas farther south, while temperatures will hold in the lower to mid 40's north of Route 6 (a temperature change of 20 degrees in 30 miles of distance!).  As the warm front surges passed the area, I expect that most towns will hit 60 south of the Michigan border, with temperatures along the border in the lower 50's.  Strong mixing in the warm sector, will promote high winds, and could warrant a high wind warning for the area with winds over 45 mph possible!  This strong mixing could cause the atmosphere to become conditionally unstable by early afternoon, and with strong lift from the cold front and remaining low level moisture, there is the possibility of low topped supercells, especially with the strongly veering winds in the lower levels of the atmosphere.  Right now the threat is pretty low of any low topped supercells, but I cannot rule out scattered showers and thunderstorms developing during the early afternoon, especially under mostly sunny skies.  By Wednesday Night, temperatures will rapidly fall in the wake of the cold front, and the comma head of the storm system will pivot through the area, causing rain and a few snow showers, with some of these showers convective in nature, with locally moderate rainfall or snowfall.  After this system, temperatures will not fall that much, with highs easily reaching the mid 40's on Thursday.  By Friday, our next storm system will be in the making and hitting our area with rain once again, and another surge of very warm temperatures.

Another Forecast Update

Since I didn't really address the rain issue in the first post, I will address it now.  According to current radar and surface observations, convective bands of localized have developed and are moving north and eastward at slow rates.  These convective bands are a result of weak mid level instability, and a unique phenomena called slantwise convection.  Intstead of regular convection, which results from upward growth of large cumulus clouds, slantwise convection develops when air moves diagonally instead of directly upward.  Since this upward motion is not intense, lightning and thunder are rare with these bands of rain, but because of the how moist the atmosphere is, and how large scale this upward motion is, heavy rainfall can result from these bands of rain.  I believe this is exactly what is occurring right now, over most of our area.  Therefore, I believe that many areas will receive periods of rain for several hours, before changing over to snow (mainly north of Route 6).  South of Route 6, rain will not change over to snow until boundary layer temperatures cool just enough so that the warm layer is not as deep, which will result from intense synoptic scale lifting and cooling of dry air at the 850 millibar level, mixing with the warmer temperatures of the boundary layer, and causing a much more unstable situation.  This could also initiate even more bands of locally heavy rain.  For this reason rainfall totals will be anywhere in the range of a quarter to a half inch or possibly more.  By early tomorrow morning, most if not all precipitation will be snow in the area with around an inch of snow possible south of Route 6, and several inches north of Route 6.  Other than that, that is the only thing that has changed since my last blog post.

Important Forecast Update

I am very sorry for not posting since Tuesday, but I have been very busy.  As for this post, I need to update the forecast, as some very drastic changes have occurred.  One important thing is that the relatively weak storm system forecast a couple of days ago, has instead become a very strong low pressure system center over Missouri, with a central pressure of at least 990 millibars.  This system has formed in response to a rapidly strengthening jet streak currently situated over the area.  Because of the jet streak, intense lifting is occuring over a widespread area, but with the little moisture that is present, only a narrow band of precipitation has set up over the Midwest, with some areas located within the more intense lifting region experiencing rain changing over to snow.  Right now, the main band of precipitation over our area is mainly rain with some mixing of snow over lower Michigan.  This initial band of precipitation will shift out of the area, with maybe even some partial clearing south of Route 30, but other than that thick clouds will persist over the area.  Intense ascent and lifting due to the temperature gradient south of the area will cause bands of rain to redevelop in most of the area, with areas north and west of Route 6 experiencing rain mixing with snow, or completely changing to snow especially across southern Michigan.  My current thinking is that the jet streak will back build and intensify, causing more intense lifting, and eventually causing most if not all of our precipitation to change to snow after 2 a.m.  The only reason why rain instead of snow is falling currently is because of temperatures near the surface are several degrees above freezing.  Other than that, as soon as we can get temperatures in lowest three thousand feet to cool at least close to freezing, snow will begin to fall.  In some areas, this will occur faster, especially in lower Michigan, far Northern Ohio, and Indiana.  For areas south of Route 6, this changeover will not happen until after late night hours, possibly as late as midnight, especially south of Route 30.  The area that has the most uncertainty right now is the U.S. 24 corridor, as models have not shown any consistency, and have not made it clear where this storm system will move to.  My current thinking is that this system is going to move just south of the area, putting us in the zone of the most intense lifting and warm air advection, which will delay the transition from rain to snow over areas south of U.S. 6.  If the storm does happen to move farther south than indicated, rain will change to snow much more quickly, and bring much higher accumulations to the area.  In the region of Northwest Ohio and Northeast Indiana, the highest snowfall totals will be observed right near the state line, with somewhat higher snowfall totals located over southern Michigan, and somewhat lower totals over far Northwest Ohio and Indiana.  A general 2-4 inches will fall over far Northern Indiana and Northern Ohio (north of Route 6), with around an inch in areas south of Route 6, with much higher totals of 6-12 inches over Lower Michigan into Detroit.  This forecast is highly uncertain as storms like these seem to surprise meteorologists in what they do, so this will be situation that I will be watching.  There is the possibility that the storm shifts south, with more substantial cold air advection in the area, causing a earlier changeover to snow and more substantial snowfall amounts.  I still see this as a possibility, but then again we would still have to worry about warm boundary layer temperatures (the layer from the surface to about three thousand feet above the surface), which would melt the snow causing a cold rain.  One thing that would help the possibility of wintry precipitation is initially dry mid level air, which with intense lifting, would cause intense cooling in the middle and lower layers of the atmosphere.  This would cause the atmosphere to become marginally unstable, causing convection, with initial rain from the convection changing over to snow.  This is why I would also expect some areas to see thunder and lightning with any convective band of rain or even snow.  If this forecast changes, I will write another post to update it.

Experimental Forecast Page.

I have created an experimental forecast page on the blog.  Anybody can access it by clicking on the tab on the front page.  I will try my best to update it at least once a day, while in severe weather or winter weather situations it will be updated two or three times a day depending on how busy I am.  Sometimes if no changes are needed, I will update the forecast only every other day.  Generally I will post a five day forecast, but if I am crunched for time, usually a two or three day forecast will appear.  If you have any questions e-mail me at storm_reportsjoshua@yahoo.com.

Forecast for the Next Three Days.

Many you have heard me say this.  I have finally given up on winter ever coming.  It's too late in the year for any nasty polar outbreaks to hit the area due to the high sun angle.  The higher sun angle is able to modify arctic air faster than a mid winter sun, causing not so extreme temperatures.  With virtually no snow cover and the lack of cold air already this winter, soil temperatures are extremely warm for this time of year, which also is a contributing factor to air mass modification.  Any polar outbreaks from here on out will be rather short lived and weak, with temperatures barely below freezing in most cases.  In a few days or perhaps today, I would like to write an article on the main reasons why this winter was not forecasted well and what went wrong.  For all you snow lovers (like me), any snowfall events will quickly melt away, because of warm soil and the lack of arctic air.  I am truly sorry for how badly my forecast was for the winter.
   Back to the present situation, even with the lack of winter across the country, some very interesting things are going on.  One of them is a rapidly strengthening storm system across the Gulf Coast in Deep South.  Here is a surface pressure image from the storm system.

As you can see a fairly decently sized storm system is located along the Gulf Coast.  This type of storm system is currently being directly fueled by the traditional jet stream dynamics, but it is being fueled by latent heat release from a enormous complex of thunderstorms north of the warm front over Louisiana and Mississippi.  This thunderstorm complex will be the culprit in very heavy rainfall and flash flooding across a large part of the Deep South.   Below is the latest radar image from the storm system.

When thunderstorm complexes strengthen in the vicinity of an upper level disturbance, the release of latent heat from condensed water strengthens the upper level disturbance, causing the surface low to strengthen, which tends to cause a strengthening of the thunderstorms in a positive feedback process, that could cause this storm system to become incredibly strong.  The release of latent heat in the Deep South, along with a baroclinic wave moving across our area currently, is also causing the rapid strengthening of an upper level jet streak currently located right over us.  This could have serious implications for the storm in the south, as the jet streak could cause explosive development of this storm system and possibly a much stronger storm affecting the Mid-Atlantic states by tonight and tomorrow.  Shown below is the current jet streak.

As you can see, right over us, about 10 kilometers above the surface, winds are raging at over 160 knots (184 mph).  It seems to me as if the jet streak is coupling with the one seen over Northern Mexico to produce these strong thunderstorms and bow echoes over the Gulf of Mexico.  As the day progresses, the storm will shift north and eastward (but not affecting our area).  Eventually, this storm will strengthen as it heads into the Mid-Atlantic states, where it will meet with a baroclinic wave currently moving over Northern Ohio.  This baroclinic wave will cause the temperatures to drop significantly not only here, but in the Mid-Atlantic states as well, paving the way for a possible snowstorm over the Appalachian Mountains and parts of Virginia, North Carolina, Tennessee and Kentucky.  Models are suggesting that the cold air will not be able to overtake the storm and cause a major snowstorm, with the cold air only clipping the edges of the storm and producing localized heavy snow in the mountains.  But if the storm continues to strengthen as it has been, a much bigger snowstorm may occur, and with even significant accumulations of snow at the surface in the Virginia and North Carolina.
    As for the forecast in our region, I expect a front to move through in the next hour or so, causing the development of stratocumulus and cumulus (this started to occur).  As the day progresses,  I believe that most of the day will be mostly cloudy, because clouds developing in the (relatively) unstable air mass behind the front, and because of lake enhancement.  Low level temperatures and the relatively unstable air mass will not be enough to generate a lake effect snow event, but convective clouds will develop and move off the lake and into most areas of Northwest Ohio and Indiana.  Although I cannot rule out a stray snow flurry or two.  By tonight, skies will clear up once again, with temperatures dropping into the lower 20's.  Tomorrow through Monday sunny skies will prevail with temperatures in the mid to upper 30's.

Support the National Weather Service.

As I have found out this afternoon, Congress has proposed to make a massive budget cut to the National Weather Service's budget.  For the meteorological community and the public, this terrible news, as some very useful weather products will be cut.  This will affect forecasts in a very bad way, because most of the meteorological community uses National Weather Service products for their own forecasts.  Weather disasters in the future may be much more damaging and life-threatening because of less forecasting.  We all remember the terrible tornado outbreaks of last year, killing over 550 people, the most in one season since the mid 1930's.  If forecasting budgets are cut, the risk for more life threatening situations becomes even higher, and many more unnecessary deaths will result.  If you want continued support for the National Weather Service, so that they may continue to improve their forecast accuracy, go to the White House's website and the sign the petition to stop the budget cuts to the National Weather Service.  Here is the link to the website. White House National Weather Service Petition (note: you will need a white house account to sign this petition.  To create a white house account is free and all you need to create an account is to give them your e-mail address and create a password.)

Forecast Update.

Most people in Northwest Ohio and Northeast Indiana probably woke up to one or two inches of fluffy snow on the ground this morning.  This snow was due to a weak upper level system embedded in the 700 millibar wind flow.  Fairly strong frontogenesis in the middle levels earlier this morning caused heavier bands of snow to develop in far eastern Indiana and Northwest Ohio, causing higher snowfall totals than most other regions.  In Antwerp, I have measured over two inches of snow on the ground, (which is what most areas reported.  Stronger forcing with this system stayed well to our south, with some cities such as St. Louis, picking up 3-5 inches of snow from the system.  All in all, this was a fairly decent, especially since it was produced by a very weak system, which would normally not produce this much precipitation.  As this system moves out, warm air advection will take place on the back side, causing temperatures to gradually rise across the area.  Due to snowmelt, however, this warming will be reduced at the surface, while in the low to mid levels of the atmosphere, temperatures continue warming.  With the amount of moisture in the atmosphere right now, due to this low level cold layer, expect as the snow ends, for the snow to change over to light freezing rain and possibly freezing fog.  By tonight, enough dry air will have arrived in the area, to cause skies to clear and temperatures to fall back into the twenties.  Tomorrow, temperatures will warm nicely under partly cloudy skies into the upper 30's and lower 40's (which may be too warm, as snow melt will cause lower temperatures).  By tomorrow afternoon, skies will begin to cloud up once again as the next system approaches.  This system, possibly a much stronger system than today's, will move into the Central Plains and Midwest.  This southern stream system will at least undergo partial phasing with the northern stream system, causing a fairly strong storm system ahead of the upper level disturbance.  Currently, the system is spinning in California, causing showers and some snow in the mountains.  Right now, the GFS model is indicating that the two systems (one in the Northern Rockies and Canada, and the other in Southern California) will not undergo phasing (two or more disturbances combining their energy and becoming one relatively strong storm system), causing a weak surface system to bring the area some rain Wednesday into Thursday.  I am going to rule out the GFS for now, as the latest upper air analysis shows that these systems are in close enough proximity to phase with each other over the Great Plains.  It all depends on how quickly the stronger southern stream disturbance scoots itself out of the American Southwest and into the Great Lakes.  This would be the solution of the ECMWF which shows a much stronger storm system, bringing heavier rain and stronger winds to the region.  If a stronger storm system, and much more powerful snowstorm would hit the Upper Midwest and Great Lakes, so we will have to keep our eyes on the situation.  In my opinion, the two systems will phase with each other, causing a strong storm system to move across the area.  By late Wednesday evening, these two systems will begin producing overcast conditions and showers across the area.  Overnight Wednesday, expect periods of moderate to heavy rain at times, with maybe an embedded thunderstorm (according to the Storm Prediction Center).  Overall rainfall will be in the range of a half inch to three-quarters of an inch, with some locally higher amounts also possible.  By Thursday morning, rain bands will still exist across the area, with the possibility of strong mid and low level frontogenesis causing the formation of heavy rain and possibly a rain/heavy snow mix especially northwest of Fort Wayne.  The low pressure center will pass through the area by Thursday mid morning, causing the dry slot to move through also, bringing a quick end to any precipitation.  Some precipitation may return for the afternoon in the comma head, but any additional precipitation will be fairly light, with a rain/snow mix possible.
   After this, a turbulent pattern will finish out the rest of the week and persist into next week, as the northern stream becomes dominant and becomes very strong.  In my opinion, this will lead inevitably lead to a meridional pattern, which is conducive for storms and SOME winter weather.  So next week and beyond, I believe that winter will go out with a big bang, with not only some last minute winter weather but maybe even some violent severe weather by the beginning of March.  As for the rest of spring, the effects of La Nina will continue on, leading to yet another wet and stormy spring, though it will probably be much warmer than last spring.  Severe weather will also be frequent around here during the mid and late spring.

More forecasts and Posts Coming Soon!

I am truly sorry for not posting this week, as I have been very busy with many things.  For right now, I will give a very brief forecast and more details will come either tomorrow or Tuesday.  After a very nice day today, tomorrow, skies will begin to cloud up, as the next system moves just south of the region.  By Monday night, periods of snow will arrive in the area, accumulating 1-2 inches, with heaviest snowfall accumulations occurring south of Route 24.  Snowfall will last through most of the day Tuesday, with most of the snow falling before 11 a.m.  By Wednesday, conditions will clear up once again, but clouds from the next storm system moving into the region by evening.  On Thursday, it looks as if another, possibly much stronger, storm system is likely to affect the area.  At this time, it looks like a rain or snow mix event, with a significant amount of precipitation possible.  More than likely, as we have seen with most storm systems this winter, it will be a mix event with everything changing to rain.  By the end of the storm system, snow may mix back in Friday before clearing up.  It is possible that the storm changes track, causes a much more significant winter weather event for the area.  With my next update, I will give more details as to what will happen with this next storm. 

Real Pattern Change on the Horizon

You probably all are tired of hearing me talk about a pattern change and that winter will finally grip the area.  Well, I'm going to stick to it.  With everything I have seen, I really do not have a doubt that a pattern will finally get set in stone.  The reason computer models have had such a bad time with the pattern is because, if you haven't already noticed, the pattern has been changing every week.  Last week, the jet stream was highly variable with more of a north-south motion instead of west-east motion, which is what caused the "mini ice storm" that many areas saw last Wednesday night and Thursday.  When the jet stream is in a meridional pattern, which is when the jet stream is variable and has rather large longwaves in the upper atmosphere, strong surface storms tend to result, due to large areas of unbalanced winds (I would like to elaborate on this, but it really is complicated to a lot of people if you don't remember high school Physics.).  Right now, the jet stream is highly zonal, which means the jet stream is very flat and not variable.  When the jet stream is zonal, disturbances move rather quickly across the United States, and they are not able to produce strong storm systems.  When the jet stream is in zonal pattern, mild Pacific air can easily flood the United States.  When I talk about Pacific air, I mean mild air that is dry, not moist.  The air mass is dry because of the drying that the air mass undergoes as it moves over the Rocky mountains.  This week, I expect a rather quiet pattern as the jet stream remains quite zonal and the disturbances will be relatively weak.  Even with that, there will be some rain Tuesday night, with rather light amounts of rainfall in the range of 0.10 to 0.25 inches of rainfall.  The latest NAM is forecasting even lighter amounts with only 0.01 to 0.10 inches likely overnight Tuesday.  The time frame for this rainfall event will be from the late evening hours Tuesday night to the early morning hours Wednesday.  It will probably not be a widespread rainfall event with most areas not picking up much rain, because of its showery nature.  As for temperatures, they will likely be well above normal for this time of year with highs in the lower 50's tomorrow.  After the weak surface cold front moves through Wednesday morning, temperatures will only hit the mid 40's Wednesday, with a gradual trend toward much cooler temperatures by the end of the week.  By the end of the week, the weather pattern looks to shift into a more favorable pattern for snow and possibly cold weather.  The first step for the change in the upper levels to happen is a strong shortwave forecasted to move out of Northwest Canada and into the United States by Thursday and Friday.  This will begin to develop into a positively tilted trough over the Central states.  This is where the forecast gets tricky.  By the time the trough begins to develop, the PNA index is expected to sky rocket at the same time.  This means that a rather strong West Coast ridge will develop, leading to significant troughing over the eastern United States.  If the trough would be negatively tilted, a major longwave trough would develop leading to a significant snowstorm across many regions and a massive arctic outbreak.  Instead the ridge will try to complicate things further.  It will attempt to close off the trough located over the plains, which at the same time will lead to significant development of possibly a rather large storm system, with three types of precipitation possible (freezing rain, sleet, and snow) by Saturday.  If cold air is involved in the system more than currently expected, a widespread heavy snow and strong winds will develop north of the surface cyclone, right in the heart of our area, with sleet, rain, and freezing rain mixing in at times.  If a more northerly solution verifies, than expect rain, possibly heavy, changing over to heavy snow and sleet in the comma cloud behind the system, with heavy snow accumulations farther north into Canada.  This also depends on if the storm system becomes significantly strong, as positively tilted troughs are notorious for producing weaker storm systems.  After that, a significant trough is expected to develop across the United States, especially in the East, and cause an arctic wave to move through after the system on Sunday, possibly bringing temperatures below normal.  This trough will become more negatively tilted with time, possibly leading to a second significant storm system by Monday.  In the long range, cold waves will become more frequent with the possibility of a rather significant and severe cold wave by mid February.  Stay tuned for further updates.

Thunderstorm Potential Tonight.

After looking through the model data, it looks the threat for thunderstorms have increased for us, so much that I believe that the SPC will extend the Slight risk area for severe weather as far north as Fort Wayne.  Right now, the Storm Prediction Center has a slight risk area all the way to just south of Fort Wayne, but still keeping us in the thunderstorm risk area.  If not for a strong low level inversion, we would have a much higher threat for severe weather, and even tornadoes.  This low level inversion is occuring to due to two things.  One, the entire still has a pretty decent snowpack, causing cold air to accumulate near the ground, and temperatures close to freezing.  Another factor is a strong low level jet which is transporting warm, moist air northward over top the cold surface air mass, which may for awhile produce freezing rain at the surface.  Through the late afternoon and evening, the surface low pressure system will rapidly strengthen into an incredibly strong low pressure system, which at the same time will cause an intensification of the low level jet, which will bring even warmer and moist air to the region.  This will likely lead to the development of dense fog in the early evening hours, just before winds begin to strengthen.  As soon as the wind strengthens, the low level inversion will rapidly weaken, allowing warm air aloft to mix towards the surface, causing temperatures to rise throughout the night, from 34 in the late afternoon to almost 50 by early tomorrow morning, along with the potential for widespread showers and thunderstorms by the late night hours.  Even though there will not be a whole lot of instability in the lowest kilometer of the atmosphere, forecast soundings indicate that a substantial amount of instability will exist above the 850 millibar layer, which would allow for the development of elevated thunderstorms, which do not form from the surface but begin at the top of the boundary layer (the layer in which friction is a huge factor and in which vegetation and surface heating effect moisture and temperature).  These storms will develop at the leading edge of the cold front.  I have several reasons why many locations around COULD see severe weather tonight.  One reason is because of the elevated instability that I was talking about, which will allow for the rapid development of thunderstorms as the cold front moves through.  Another factor in my forecast are strong mid level winds of over 100 mph, which will drive a strong QLCS (quasi-linear convective system- a squall line that is nearly linear in shape but can still contain damaging winds, hail, and tornadoes.  They usually move through faster than typical squall lines, reducing the threat for heavy rain somewhat.).  These strong winds could potentially mix to the surface if the inversion is weaker than what is forecast.  Severe weather would be more likely if the warm front moves farther north than what is anticipated but the limiting factor here is our fresh snow cover and frigid ground, which is causing a low level cold wedge to remain strong.  Another factor is the the Low Level Jet Stream, which is originating from the Gulf of Mexico, transporting warm, moist air northward into our area.  This will bring plenty of moisture for the development of heavy thunderstorms and will enhance the development of the squall line.  The LLJ will not only enhance the development of thunderstorms, but also very strong non-thunderstorm winds, especially later in the morning Monday as the lapse rates steepen due to cold air aloft and relatively warm surface air.  Snow and rain will pivot around the trough axis through Monday evening before tapering off after the storm system leaves the area.  If all of the above factors are in place, I expect a heavy rain threat, a slight severe weather threat, and high winds to be in place.  If the NAM and RUC forecasts are correct, we may be seeing scattered showers and thunderstorms into the area by 8 or 9 p.m. tonight.  Overnight, farther west, a powerful line of severe thunderstorms will develop and move northeast right into the area.  Down south, in western Tennessee, Mississippi, Arkansas, and Southern Missouri, conditions will be just right for a widespread outbreak of severe weather, including strong, long tracking tornadoes, much like several of last year's deadly tornado outbreaks.  Back home, the squall line will race to the northeast, with damaging winds and hail possible, with heavy rainfall of up to an inch is possible in some areas.  The damaging winds are questionable, as low level inversions tend to damper the effects of damaging winds.  But I can remember a time last year when we had a substantial inversion and a severe weather event occurred, while damaging winds were widespread across the area.  So it is still a possibility that damaging winds could be widespread with thunderstorms tomorrow morning.  Hail is also a possibility but not likely at this time.  Up to an inch of rain is possible with the squall line, but most areas will likely pick up in between a half and a three quarters of an inch.   This will likely lead to flooding problems due to snow melt and an already saturated ground.  As mentioned before, scattered thunderstorms are also possible before this main squall line moves through with fog likely before the line moves through also.  This squall line will likely arrive in the early morning hours tomorrow morning in the time frame of 3- 6 a.m.