AFTERNOON-OVERNIGHT: Clouds and areas of rain continue working across zones 1 and 5 this morning. This is ahead of the initial cold front that is still in place around the IL/IN state line.
Rain and a few t’storms will continue to move northeast and east along the cold front. Mainly across eastern/southern Indiana and into Ohio. Across western Indiana, a lull in activity will continue through early afternoon. However, by 1-2 PM some isolated to scattered areas of rain look to redevelop across the area.
Rain and some t’storms will continue across the forecast zones through the afternoon. By 5-6 PM the initial front will be in place across central Indiana, ahead of the front across eastern Indiana and into Ohio more widespread/concentrated areas of rain will be present. To the west of the front, across western Indiana more scattered rain and storms will be moving through.
By 9-10 PM rain and storms will be moving across the zone forecast area. The better chances for rain and some storms will exist across western/southern Indiana just along and ahead of the front.
While widespread severe weather is not forecast today a couple strong to a few severe storms will be possible. Mainly across eastern Illinois and western Indiana. Aloft a 500 mb wind max will be surging through at 45-55 mph.
There is some sunshine moving in across Illinois, with that headed this way, afternoon instability is looking more promising. The HRRR model does depict pockets of 900-1200 J/Kg of CAPE across eastern Illinois and western Indiana this afternoon/evening. The better chances for some strong/severe storms would exist where the higher instability and better upper-level winds intersect across western Indiana.
Through the overnight, the front will move through Indiana, entering the Indianapolis area by 2-3 AM Friday morning. Some scattered rain and a few storms will be moving across the zones by this time.
Lows overnight will be around 50 north to the mid 50’s south.
Through the evening into the overnight times of heavy rain will be possible across both zones 1 and 5. Models right now are more aggressive with this heaviest rain occurring over southern Indiana in zone 5. This is where localized areas of 1.25-1.75” could occur, although the latest NAM 4 km in much more aggressive.
Farther to the north across zone 1 and into Ohio, totals look to be less with .25-.60” likely being the average. However, some localized pockets of heavier amounts will be possible under any t’storm that develops.
FRIDAY: By 7-8 AM Friday morning the front will be off to the regions east. However, the surface and upper-level low will still be meandering around the area. This will allow some isolated showers to continue.
Through mid-day showers and perhaps a couple of thunder showers will develop across southern/eastern Indiana and into Ohio. This will be thanks to that low that continues moving across the area.
Through the afternoon into the evening isolated to widely scattered areas of rain will continue across southern Indiana and southern Ohio. By 5-6 PM the NAM 4km shows some of those moving across the area.
Highs on Friday will be a bit cooler with temperatures topping out in the low 60’s north to near 70 south.
Through the evening a few isolated showers will remain, but as the sun sets these will start to fade out. By 10-11 PM only some very light hit and miss showers will remain.
SATURDAY: An area of high pressure will ridge into the region from the north late Friday night into Saturday. This will set the stage for a very nice weekend! As the high builds in and dry air moves in with it rain will move out and clouds will erode.
This will set the stage for sunny to mostly sunny skies on Saturday. Highs will warm into the mid 60’s northeast to low 70’s south.
SUNDAY: The area of high pressure will move to the east. To the west a large area of low pressure will develop and move across the Great Plains. An associated warm front will be in place to the northwest of zones 1 and 5 on Sunday. While this will allow for some clouds to move in, but no rain is in the forecast.
With the warm front north, we will return to a southerly flow of air, which will mean warm temperatures. Highs on Sunday will be in the low 70’s east to upper 70’s west!
MONDAY – TUESDAY: An area of low pressure will be set to move through the Great Lakes region late Monday through Tuesday. On Monday this will allow for scattered rain and storms to form across the forecast area.
Highs will remain warm with temperatures in the 70’s.
Monday night into Tuesday the cold front will move through, so a better chance of some rain/storms will exist along the front overnight.
LONG RANGE (MID-LATE NEXT WEEK): Active weather looks to remain across the region. Rain, storms, and even severe weather are possible mid to late next week. The SPC has already outlined western Illinois in a severe weather risk next Wed. Obviously timing and exact locations will need ironed out over the next week or so.
Beyond that, the more active pattern will continue with perhaps another severe weather event around the April 30 – May 2nd time frame. The models have been persistent with a storm system; details are just too far off to pinpoint much at this time.