(11:00PM Thur, July 27th 2023) Thursday night update regarding multiple disturbances and storm systems that will continue to move through the region through Saturday, along the northern periphery of a ridge in place across the region. This pattern will continue to support daily chances for rain/t’storms and severe t’storms across portions of the state during this period, through Saturday.

Update…
•With this update severe t’storm probability areas have been slightly adjusted on tonight’s forecast, based on real time information and trends.
•With this update we have upgraded severe t’storm probabilities across portions of Northern Illinois on Friday/Friday night’s forecast.
•With this update we have issued our first forecast for Saturday, with a threat for severe t’storms possible across Southern Illinois.

​Timing & Location…
•Tonight – Early Friday Morning, July 27-28th: Much of Illinois.
•Early Friday Morning – Early Saturday Morning, July 28-29th: Northern & Central Illinois.
•Early Saturday Morning – Saturday Night, July 29th: Southern Illinois.

Impacts…
•A level 1 severe t’storm risk is in place across much of Illinois, from tonight through early Friday morning. Isolated severe t’storms will be possible, posing a risk of damaging winds and large hail.
•A level 1 to 3 severe t’storm risk is in place across Northern and Central Illinois, from early Friday morning through early Saturday morning. Isolated to scattered severe t’storms will be likely, posing a risk of damaging winds, large hail and an isolated tornado.
•A level 1 severe t’storm risk is in place across Southern Illinois, from early Saturday morning through Saturday night. Isolated severe t’storms will be likely, posing a risk of damaging winds and large hail.