Latest on next week's severe weather potential across northern Illinois

Weekend Rain Chances:

Most of our Saturday will remain dry. After some patchy fog, cloud cover will increase through the day, and that could lead to a spotty rain shower during the afternoon. Rain chances become a bit higher this evening and overnight, with the best chance for more widespread rain arrive late Sunday into the the first few hours of Monday morning.  

Severe weather potential looks very limited, with the highest chances ending up across parts of the plains including Missouri, Iowa, and Wisconsin. Looking ahead to next week, the overall pattern will become more active, resulting in what could be a multi-day stretch with severe potential. 

   

Monday:

In their latest outlooks, the Storm Prediction Center placed across along and north of the Illinois-Wisconsin border under a Level 2 of 5 Slight Risk for scattered severe thunderstorms. 

One of the biggest question marks will be whether storms are able to break what is known as the "cap". This is a layer of warm up that develops a few thousand feet above the surface that acts as a "lid" on the atmosphere, preventing storm development. Normally, you want temperatures to cool the further up you go into the atmosphere. But with a warm layer sitting overhead, storms can't bubble up and become mature or severe. IF storms manage to develop, hail and damaging winds will be the main concerns Monday evening into Monday night. 

Tuesday:

Tuesday is still looking like the best day locally for strong to severe storms. The Storm Prediction Center has a massive 15% severe risk (equivalent to a level 2 of 5 Slight Risk) stretching from Fort Wayne, Indiana to Green Bay, Wisconsin to central Texas. This does include the Stateline in its entirety. 

Locally, the severe threat mainly is tied with the incoming low pressure system and the associated warm front. Uncertainties reside with how things go in the upper-levels of the atmosphere as we'll need to monitor how those waves evolve. This leaves that spark or lift in question but there will be no issues with wind shear, storm fuel, and moisture. Regardless, all severe modes, including a few tornadoes, may be possible along the warm front. Wednesday has been down-trending as the focused area for strong to severe storms has shifted southward.