(11:15PM – Wednesday, August 14th, 2024) Wednesday night update on a storm system that will move through the region, which will bring multiple rounds of rain and t’storms to the state from early Thursday morning through early Friday night. Severe t’storms will be likely with some of this activity across specific outlooked areas during specific timeframes.
Update…
•With this update on the severe t’storm forecast for Thursday/Thursday night, little changes were needed, as the going forecast is on track.
•With this update, we have issued our first severe t’storm forecast for Friday.
Timing & Location…
•Early Thursday Morning – Early Friday Morning, August 15-16th: All of Illinois.
•Early Friday Morning – Early Friday Night, August 16th: Northern, Eastern & Southern Illinois.
Impacts…
•A level 1 to 2 severe t’storm risk is in place across much of Illinois from early Thursday morning through early Friday morning for the likelihood of isolated to widely scattered severe t’storms. Damaging winds, large hail, and an isolated tornado will be the threats from activity.
•A level 1 severe t’storm risk is in place across portions of Northern, Eastern, and Southern Illinois from early Friday morning through early Friday night for the likelihood of isolated severe t’storms. Damaging winds and hail will be the threats from activity.
Discussion…
•With a storm system moving through the region, multiple rounds of rain and t’storms are expected to traverse the state from early Thursday through early Friday night.
•For the timeframe of early Thursday morning through early Friday morning, an initial round of activity will track across the state from late tonight/early Thursday morning through midday Thursday. While organized severe t’storm activity is not expected with this first round, a non-zero strong/severe t’storm threat cannot be ruled out. In the wake of the first round of activity, clearing and atmospheric recovery will occur. A second round of t’storms will develop in scattered fashion Thursday afternoon across a large corridor of Iowa, Missouri, and Illinois. This activity will then track across portions of the state from Thursday afternoon through early Friday morning. Environmental conditions will be supportive of a severe t’storm threat with some of this activity across the specific outlooked area during this timeframe.
•For the timeframe of early Friday morning through early Friday night, remaining activity may still be ongoing early Friday morning across Eastern and Southern Illinois, potentially with a non-zero strong/severe t’storm threat. For the reminder of the day, multiple forcing mechanisms moving through the region will aid in the development of isolated to scattered showers and t’storms developing in the region, including across portions of the state. Northern, Eastern, and Southern Illinois will be most favored for this round of activity from Friday afternoon into early Friday night. Environmental conditions will be supportive of a severe t’storm threat with some of this activity across the specific outlooked area during this timeframe.
