(11:45PM – Monday, March 31st, 2025) As a potent storm system moves through the region, a few waves of shower/t’storm activity will be likely across the state between early Wednesday morning and Wednesday night. Severe t’storms will be possible with some of this activity.
Timing…
•Early Wednesday Morning – Wednesday Night, April 2nd.
Location…
•All of Illinois.
Impacts…
•A level 1 to 3 severe t’storm risk is in place across much of the state for the likelihood of isolated to scattered severe t’storms.
•All modes of severe weather will be possible, including large hail, damaging winds and a few tornadoes. The tornado threat will be maximized across Eastern and Southern Illinois.
•Environmental conditions will be supportive of the possibility of occurrences of: Strong tornadoes, long track tornadoes, damaging winds 75MPH+, corridors of widespread/significant wind damage and hail larger than 2.00”.
Discussion…
•Multiple waves of shower/t’storm activity will be likely across the state between early Wednesday morning and Wednesday night, as a storm system moves through the region.
An initial round of scattered showers and t’storms will develop and traverse portions of Northeast Missouri, Iowa, Northern and Central Illinois Tuesday night into early Wednesday morning, as a warm front begins to lift northward and warm air advection occurs. An isolated strong/severe t’storm will exist with this activity, mainly after midnight Tuesday night (Early Wednesday morning). Hail will be the main threat should any isolated strong/severe t’stroms occur.
Beyond this, a weakening and broken line of rain and t’storms will enter the Northwestern-Western-Southwestern Illinois early Wednesday morning. This activity will be remnants of severe t’storm activity expected to occur across the Plains on Tuesday evening and Tuesday night. An isolated strong/severe t’storm threat cannot be ruled out with this activity, with wind and hail being the threats. As this weak activity spreads further across the state on Wednesday morning, it will throw a wrench into how exactly the rest of the day will play out. There are a few possible scenarios that could potentially result. The most probable scenario at this moment in time is that this early-day activity will fester throughout the morning across the state, with reintensification and development of new activity to occur in the undisturbed open warm sector, which will reach into Eastern and Southern Illinois. Once this occurs, this activity will traverse these portions of the state into early Wednesday night. Further to the north and west, across much of Northern and Central Illinois. The threat is dependent on enough recovery occurring, potentially allowing for another broken line of shower/t’storm to develop along the main advancing cold front. As of this time, while this potential does exist it appears lower-end at this moment. Should this activity occur and maintain, all modes of severe weather would be possible, with lower coverage severe potential.
In summary…There are still many questions with the evolution of the severe t’storm threat across the state for this period. As we move closer to the event and with additional weather guidance data coming in, adjustments to the forecast will be likely.
