Storms possible this afternoon

After an unusually warm afternoon (in some areas), thunderstorms are erupting to the west and quickly moving eastward.  With building surface based instability and lingering deep layer shear across the area, areas mainly southeast of U.S. Highway 24 could receive severe weather this afternoon and evening.  Originally, I was not anticipating the warm front to move north of U.S. 6, but it did, and temperatures in Antwerp and surrounding areas have soared into the lower 80's, with dew points in the lower 60's.  With this unexpected surge of warmth and moisture, moderate instability has developed in areas south of U.S. 6.  This could pose a threat for severe weather to some parts of the area, as the Storm Prediction Center has placed parts of the area in a Slight Risk outlook.  They are expecting mainly damaging winds and possibly a few supercell thunderstorms.  Over the next few hours, storms will continue to become more widespread throughout the late afternoon and evening hours, with eventually all convection ending with a line of thunderstorms moving through by about 6:30 p.m.  Overnight, skies will begin to clear with temperatures falling into the mid-50's, as a weak cold front pushes through the area.  Tomorrow, partly cloudy skies will prevail with temperatures rising into the mid to upper 70's and possibly 80's, depending on the degree of cloud cover.  Humidity levels will be much lower tomorrow, so don't expect it to be as humid as today.  By Wednesday, temperatures will approach the upper 80's with high humidity levels returning, along with a slight chance for thunderstorms.

Drought possible. Record warmth for this week.

I have very bad news for those of you out there who are farmers.  Looking at the latest long-range forecast information and current weather information, I can see that a large chunk of the area may officially go into drought status for the first time since last summer.  One of the reasons for this is the incredibly dry April and March that we have seen this year.  In March, record warmth and lack of rain lead to the ground drying up, with any meager moisture leftover from the relatively snowless winter evaporating as incredibly warm air poured into the region.  In April, relatively mild air continued, but not to the extent as in March.  March may have been relatively dry, but April was incredibly dry with only 0.84 inches of precipitation since the beginning of April to the 30th.  Now, on a side note, we may see a few showers and thunderstorms before the month ends tomorrow, but I highly doubt we will see anything more than a half an inch.  Normally, April receives between 3.5 and 5 inches of rain.  Last April, in comparison, saw a near record of 5.44 inches of rain, leading to the wettest spring on record.  This spring, we are nearly 4 inches below normal, but temperatures are well above what they were last year.  As for the future in the next several months, climate models, the ones that were indicating record warmth during the past winter, are showing yet another dry and hot summer across the area, with most of the precipitation and storm systems impacting the southern United States.  In fact, this May originally was expected to be relatively cool and wet in most of the Northern United States, but now with the overall pattern shift from a dominant New England trough to a more dominant central plains ridge, I expect very warm conditions for a good part of May.  This leads me to this week's forecast.  Because of the development and eastward movement of a very strong upper level ridge, warm air will begin to surge northward by tonight and tomorrow, with temperatures jumping from the mid 60's today, to the low and middle 70's tomorrow.  On this initial wave of warm air (more technically high theta-e air), showers and thunderstorms will develop tonight and tomorrow, with the heaviest rain and pushing northwest of here.  It is possible that the warm front will lift past the area tomorrow (depending on the relative strength of the shortwave moving into the area.), bringing much warmer temperatures than originally forecasted, which could mean the possibility of stronger thunderstorms, and high temperatures in the mid to upper 70's or even 80's (this is highly unlikely at this point.)   

By Tuesday, lingering widespread showers and thunderstorms will taper off in the morning hours, possibly leading to clearing by afternoon.  This means that temperatures could rise into the upper 70's on Tuesday, depending on the degree of cloud cover.  By Wednesday, most thunderstorm will have cleared out, with only a slight chance for thunderstorms.  Both Wednesday and Thursday will be the muggiest and warmest days of the week with high temperatures in the mid 80's, along with dew points in the mid 60's.  On those days, model guidance still suggests the possibility of temperatures reaching much higher than what is currently forecasted.  In other words, it is possible that temperatures reach the upper 80's and into the 90's on Wednesday and Thursday.  On both of these days, nighttime lows will only fall into the mid 60's, making for warm and muggy nights (at least in comparison to normal).  By Friday, a cold front will approach from the west, bringing a renewed chance for showers and thunderstorms.  Temperatures on Friday will be slightly cooler than on Thursday, but it will still be fairly warm with highs in the upper 70's and lower 80's.  By Saturday, as the cold front moves through, temperatures will only cool into the mid 70's with sunny skies.  The cold front will become stationary in southern Indiana, possibly moving back northward as additional shortwaves move along the boundary, bringing the possibility of warm weather back into the picture by next week.