(11:45PM – Friday, August 15th, 2025) Severe t’storm threat on Saturday/Saturday night…
Timing…
•Saturday Morning – Sunday Morning, August 16-17th.
Location…
•Northern & Eastern Illinois.
Impacts…
•A level 1 severe t’storm threat is in place across portions of Northern and Eastern Illinois, for the threat of isolated severe t’storms. Damaging winds and hail will be the main threats with activity.
Discussion…
•A complex scenario will exist on Saturday/Saturday night, with multiple potential outcomes possible. The below scenarios are just a few of several on the table. We will not have a better grasp on how exactly things will unfold on Saturday/Saturday night until at least Saturday morning.
-Scenario #1: An MCS across South Dakota/Nebraska tonight (Friday night) will top a ridge in place across the region. This complex will then dive southeastward on the backside of the ridge, re-strengthening through the day, eventually clipping across portions of Northern and Eastern Illinois between midday Saturday and early Saturday night.
-Scenario #2: The South Dakota/Nebraska MCS from tonight (Friday night) ends up staying well north, across Wisconsin and Michigan, on Saturday. Additional development of rain/t’storm activity occurs to the south, including across portions of Northern Illinois. This activity would then have the opportunity to develop into one or more clusters, then affecting portions of Northern and Eastern/Central Illinois into Saturday night/Sunday morning.
-Scenario #3: Multiple rounds/clusters of rain/t’storm activity affects portions of Northern and Central Illinois, between Saturday morning and Sunday morning.
-Scenario #4: The South Dakota/Nebraska MCS from tonight (Friday night) stays well north of the state on Saturday. With the ridge in the region flexing into the area, outside of a few summer-like isolated ‘popcorn’ showers and t’storms across the state, things stay uneventful.