Very active and stormy weather pattern Sunday through Tuesday

The quiet beginning to severe weather season could soon be coming to an end beginning late Saturday night.  A strong, but slow moving, storm system will have much of the U.S. under its control through the end of this upcoming week.  Low pressure will rapidly strengthen in Nebraska late Saturday night and Sunday pulling in a fairly unstable air mass south of a warm front putting places like Iowa, central Illinois, Missouri, Arkansas, eastern Oklahoma and Texas under a severe weather threat Sunday afternoon.  That threat will then shift slightly east Monday as the greatest instability follows the strongest part of the jet stream.

Closer to home, thunderstorms and heavy rain will be likely Sunday night and Monday afternoon as the warm front lies between the I-88 and I-80 corridor.  We will, however, have to watch just how far north the warm front is able to reach.  If it can reach a little further into northern Illinois then the strong to severe storm threat will shift further north with it.  If, however, the front stays to the south, east winds off of Lake Michigan will provide a drier and more stable air mass keeping a lot of the severe weather at bay. 

As the old saying goes: 'The devil is in the details' and that's surely the case with this next storm system.  While the greatest severe weather threat will stay south of here, it'll be close enough late Sunday and Monday.  Make sure you stay alert over the next couple of days.  As far as rainfall, the Gulf will be wide open for moisture to lift north through the Mississippi River Valley leading to potentially over two inches of rain falling from Sunday through Tuesday in northern Illinois and southern Wisconsin.  With this expected rainfall, area rivers and streams could see a rise in levels by the middle of the week.  If you live near an area that does experience flooding, make sure you remain alert to any rising water levels on those rivers.