(11:30PM – Monday, April 13th, 2026) Severe t’storm threat continues through early Thursday…
⚠️Update…
•With this update cycle, we have adjusted the forecast for the remainder of tonight through early Tuesday morning based on trends and real time observations.
•With this update cycle, little changes were needed to the going forecast for Tuesday through early Wednesday morning, as things are on track.
With this update cycle, we have issued our first forecast for Wednesday through early Thursday morning timeframe.
⏰📍Timing & Location…
•Tonight – Early Tuesday Morning, April 13-14th: Northern, Central and Southwestern Illinois.
•Tuesday Morning – Early Wednesday Morning, April 14-15th: Northern & Central Illinois.
•Wednesday Morning – Early Thursday Morning, April 15-16th: Much of Illinois.
⚡️Hazards…
•A level 1 severe t’storm threat is in place across portions of Northern, Central and Southwestern Illinois from tonight through early Tuesday morning, for the threat of isolated severe t’storms. Damaging winds and hail will be the main severe weather threats.
•A level 1 to 3 severe t’storm threat is in place across Northern and Central Illinois from Tuesday morning through early Wednesday morning, for the threat of isolated to scattered severe t’storms. All modes of severe weather will be possible, including large hail, damaging winds and a few tornadoes. Some significant severe t’storms will be possible across Northern and Central Illinois, capable of producing very large hail (2.00″+) and/or a strong tornado.
•A level 1 severe t’storm threat is in place across much of Illinois from Wednesday morning through early Thursday morning, for the threat of isolated severe t’storms. All modes of severe weather will be possible, including large hail, damaging winds and a few tornadoes.
✔️Summary…
•Tonight – Early Tuesday Morning… A large complex of rain and t’storm activity is ongoing early tonight across Central/Southern Wisconsin, Southeastern Minnesota and Northeastern Iowa. This complex, in a weakening phase, will clip across portions of Northern and Eastern Illinois tonight and into early Tuesday morning. Some development of additional scattered shower and t’storm activity may also occur on the western fringes of this complex, across other portions of Northern and even Central Illinois. Additionally, a complex of rain and t’storm activity in Central Missouri early tonight may attempt to push towards the St. Luois metro area later tonight, in a weakening phase.
•Tuesday Morning – Early Wednesday Morning… Some lingering scattered shower and t’storm activity may be ongoing on Tuesday morning across portions of Northeastern and Eastern Illinois. In the wake of this activity, scattered showers and t’storm are expected to develop on Tuesday afternoon ahead of frontal boundary, across portions of Southern Wisconsin, Eastern Iowa and Northwestern Illinois. This activity will then traverse Northern Illinois through Tuesday night/early Wednesday morning. Some of this activity may also make it into portions of Central Illinois by late Tuesday night/early Wednesday morning as well. Otherwise, while a rogue shower/t’storm cannot be ruled out Tuesday afternoon/evening across Central Illinois, shower and t’storm activity that develops across Missouri on Tuesday afternoon may also move into portions of Central Illinois Tuesday night/early Wednesday morning.
•Wednesday Morning – Early Thursday Morning… Multiple areas and rounds of rain and t’storm activity will be likely across the state from Wednesday morning through Wednesday night/early Thursday morning, leading for a messing evolution overall. Because of this, we have opted for a broad-brush of lower severe t’storm probabilities at this time.
