Strong to severe storms return to the Stateline mid-week

 The active early Spring pattern is set to continue this week with the risk for strong to severe storms locally both Wednesday morning and afternoon. But the afternoon threat is conditional on what we exactly see early Wednesday morning. So, let's break it down:

Monday evening:

Skies will remain mostly clear as high pressure slides across the northern Great Lakes. Temperatures that warmed into the upper 40s and low 50s during the afternoon will fall as the sun sets and the northerly breeze eases up. This will allow overnight lows to dip into the upper 20s overnight. Skies will remain mostly clear through the night, with only a few clouds expected early Tuesday morning.

Tuesday morning and afternoon:

Sunshine will greet us Tuesday morning but expect cloud cover to increase through Noon, turning skies mostly cloudy during the afternoon. The afternoon hours will be dry as a southeast wind helps warm temperatures into the upper 40s. This is still below our average high of 54 degrees for April 1st. By late afternoon a few sprinkles and/or light rain showers will develop, with a few snowflakes mixing in near and north of the state line. No accumulations or impacts are expected from that. Scattered light showers will continue through the rest of the evening as temperatures hold steady, rising through early Wednesday.

Tuesday night/early Wednesday morning:

The threat for isolated to scattered severe storms will be possible during the early morning hours Wednesday as the remnants of storms that develop late Tuesday evening over the Plains shift east. A rather strong upper-level system will move across the Plains and Midwest as increasing winds and instability occur out ahead of it.

Elevated thunderstorms will develop early Wednesday morning as a warm front approaches from the south. These storms may be strong enough to produce hail, some of which could reach severe limits (one inch in diameter). While the highest risk is for hail, damaging wind gusts could also occur. It looks like the window for these storms to move through would begin just before sunrise, possibly lasting through late morning.

The Storm Prediction Center has placed most of northern Illinois within a 'slight' risk for severe storms, with a 'marginal' risk extending into southern Wisconsin.

Wednesday afternoon/evening:

The threat for any additional thunderstorms Wednesday afternoon and evening remains conditional on what occurs Wednesday morning. Given the strong dynamics of the incoming storm system the threat is there locally, but if the morning activity is slow to leave it would likely limit how much we are able to recover for additional storms to redevelop during the late afternoon and evening. The trend has been for the morning storms to last a little longer, pushing the afternoon and evening threat a little further to our east and southeast. But that could change.

If, however, the storms are faster to move out and the cold front is slower to move in then our severe threat during the late afternoon and evening would increase.

There is an 'enhanced' risk for severe storms for Wednesday afternoon for much of northern Illinois. A 'slight' risk is in place for southern Wisconsin.

The way things look now the thunderstorms during the morning may have the higher severe potential, but we cannot let our guard down for the afternoon. Please make sure you are staying up to date on the forecast and be ready for the storms as they move in Wednesday morning.