Rainfall Update

Well, it turns out that weak upper level disturbance over the Gulf of Mexico may have a much more profound effect on our weather by Monday and Tuesday.  By my forecast reasoning, I expect that the weak upper level circulation will shift northward and weaken.  The circulation of the strong upper level trough over Canada (as seen on water vapor imagery) coupled with the weakening low over the Gulf of Mexico, will enhance deep moisture transport northward from the Gulf of Mexico, especially after mid-morning Monday.  In my opinion, models are still too fast with the cold front progression through the area, which is why they continually forecast temperatures much cooler than Sunday.  With a slower frontal progression (due to lack of upper level support), clouds will take a little longer to reach the region.  With deep moisture in place by Monday at noon, conditions may feel humid and uncomfortable, with dew points approaching the upper 60's and lower 70's by late afternoon.  By 5 or 6 in the afternoon, depending on the strength of upper level forcing, numerous showers and thunderstorms look to form in the moist air mass, which could hit the area for several hours.  This time, with a lack of deep layer shear, slower frontal progression, and strong storm relative inflow, some areas in the region (especially east of Fort Wayne) could see heavy rainfall amounts, especially in the overnight hours Monday.  Usually, lack of strong upper level storm-relative winds cause slow storm movement and back-building storms, which enhance rainfall amounts.  Also, precipitable water values will be over 2 inches, which indicates an unusually moist air mass.  In some areas, this might turn out to be the heaviest rainfall since January!

Much Warmer Weather.

We will not have to worry about cooler weather probably for quite a while, as most of the arctic air has shifted to the very northern reaches of the earth, with westerly winds in Canada keeping the coldest air "locked" up.  This will also mean a lack of strong storm systems, meaning that any severe weather and for that matter, rainfall will be rather limited most likely through the rest of the month.  I still expect chances for thunderstorm complexes on the edges of upper level ridges (commonly called the "Ring of Fire").  This doesn't even seem that likely this year, especially with how quickly these ridges of warm air expand eastward, pushing most rainfall into the Northern United States and into Canada.  As for the next few days, expect sunny skies with our hot June sun, allowing for rather warm temperatures.  Tomorrow, Saturday, June 9, 2012, expect highs to jump into the lower 90's with excellent fire weather.  I would definitely recommend not planning any bonfires tomorrow, as the relative humidity will likely drop to around 20% by afternoon, combined with the much above normal temperatures, and already drought conditions across most of the area, this would make for large wildfires if anything gets out of hand. By Sunday, I would not worry as much about fire weather, as I expect return flow from the Gulf of Mexico will cause dew points to rise into the lower 60's, which would cause much higher relative humidity.  Besides that, I expect highs likely rising above what the MOS guidance would have, with highs approaching 92 or 93.  Increasing mid level clouds and higher moisture content will only allow temperatures to drop into the upper 60's and lower 70's.  On Monday, depending on the amount of cloud cover and thunderstorm development, temperatures will likely make to at least the mid or upper 80's, especially east of Fort Wayne.  Moisture will be on the increase, but I have a hunch that computer models are overdoing the amount of moisture present, which probably means that guidance may also be overdoing cloud cover and thunderstorm activity, especially with how far north the system will be located (Central Canada).  More than likely, the strongest areas of lift will occur well north of the area, and with lower moisture, most areas will probably receive some rain, but not a whole lot, if any.  This will likely lead to a worsening of drought conditions across the area. An upper level low (a rather weak one at that) could lead to enhance moisture transport into the region, which could bring a better chance for rain, but at this time, I really don't think that is all that likely.  In opinion, most of the rainfall will end by noon Tuesday (if it hasn't already).  If most places do not get much rain, I expect dry conditions to continue well into next week, with temperatures in the low 80's for a few days before yet another heat wave appears on the horizon, which at this time appears to reach the area by Friday and Saturday, bringing 90+ heat to the region.  This next heat wave looks quite a bit more incredible than the one this weekend, for several reasons.  One, with the incredibly dry conditions continuing, along with the intense June sun, temperatures can rise rapidly.  Two, a break in the Atlantic block, and then a restrengthening of the block will keep a strong ridge located over the area for at least several days, allowing for warm temperatures and sunny skies to prevail.  Three, moisture transport will be rather limited into the region (even though dew points may be quite high on some days), which will allow for limited cloud cover and virtually no thunderstorms.  Four, even if moisture transport is enhanced, thunderstorms will not be likely, as a mid level cap from subsiding air within the zone of high pressure will limit little or any clouds.  All in all, this will all just act to enhance the ongoing dry conditions across the area, with moderate or severe drought likely overspreading the region by mid or late June (assuming little or no rainfall).  For the most up to date information: visit Midwest Drought Monitor.

Dry, Quiet Pattern Prevails

After a very turbulent week, featuring everything from record heat, to well below normal temperatures, to rainy afternoons, and windy days, this week will be rather relaxing and enjoyable.  This week, I am expecting sunshine on most if not all of the days.  Even though a cold front will likely move through the area late tonight into tomorrow morning, a huge temperature drop is NOT expected, with temperatures only dropping into the mid 70's.  This is how I expect temperatures to remain through most of the week, with a gradual moderating trend after Wednesday.  During the same timeframe, I am not expecting any precipitation, with only the possibility of a few showers ahead of the shortwave tomorrow, but mainly southwest of here.  By next weekend, an upper level ridge will build into the region, resulting in increasingly warmer temperatures.  In fact, temperatures will most likely reach the 90's by next Sunday, with a week or more possible of above normal warmth and humidity.  Because of the overforecasted rainfall amounts on Friday, the drought was not impacted and will likely continue to rage in the area, only getting worse over the next week and a half or so.  In fact, light to moderate drought has already hit areas in Northeast Indiana, with this area likely to spread eastward as the week moves on.  Enjoy the weather!