(10:00AM Mon, July 17th 2023) Monday morning update, regarding multiple disturbances and storm systems that will move through the region through Thursday, along the southern flank of mean troughing in Canada/Great Lakes, and along the northeastern periphery of a ridge in place across the Desert Southwest/Southern Plains. This pattern will continue to support daily chances for rain/t’storms and severe t’storms across portions of the state during this period.

Update…

•With this update we have increased severe t’storm probabilities to a level 2 (Widely Scattered) severe t’storm threat across portions of Southern Illinois on today/tonight’s forecast, based on real time information and the latest model guidance.

•With this update we have increased severe t’storm probabilities to a level 2 (Widely Scattered) severe t’storm threat across portions of Southern Illinois on Tuesday/Tuesday night’s forecast, based on latest model guidance. Slightly higher coverage severe t’storm potential looks increasingly likely.

​Timing & Location…

•This Morning – Early Tuesday Morning, July 17-18th: Central & Southern Illinois.

•Early Tuesday Morning – Early Wednesday Morning, July 17-18th: Southwestern & Southern Illinois.

•Wednesday & Thursday, July 19 & 20th: TBD.

Impacts…

•A level 1 to 2 severe t’storm risk is in place across Central and Southern Illinois, from this morning through early Tuesday morning. Isolated to widely scattered severe t’storms will be likely, posing a risk of damaging winds and large hail.

•A level 1 to 2 severe t’storm risk is in place across Southwestern and Southern Illinois, from early Tuesday morning through early Wednesday morning. Isolated to widely scattered severe t’storms will be likely, posing a risk of damaging winds and large hail.

•A severe t’storm risk will exist on Wednesday and Thursday as well. More specific information regarding potential these days is to come in future updates.