Storm threat returns Monday afternoon

 

Skies will continue to clear Sunday night following a few showers and isolated thunderstorms that moved through earlier in the evening. Nothing widespread, but the showers that moved through did produce a few brief downpours and frequent lightning. Temperatures will only drop into the mid to upper 60s as southwest winds increase on the heals of a strengthening low level jet. Not only will this keep our temperatures on the warmer side, it'll also help to pull in more moisture through Monday morning as dew point temperatures near 70 degrees. We may not see a big rise in the actual air temperature, but the humidity will increase significantly. This could eventually lead to a few thunderstorms during the afternoon and evening.

A cold front approaching from the northwest Monday will pass through southern Wisconsin and northern Illinois during the afternoon. Ahead of the cold front, we may see a few showers and isolated thunderstorms mid-morning from a weakening storm complex currently developing over the central Plains Sunday evening. A slightly higher risk for a few stronger storms exists across west-central Illinois with this complex. It's entirely possible that the storm complex weakens enough that all we see Monday morning is an increase in cloud cover locally. If that's the case, temperatures will warm into the upper 80s/low 90s and that could push the heat index close to 100 degrees for some.

As the cold front nears during the afternoon instability will gradually build. There is a risk for a few strong/severe storms, especially south of Rockford, during that time. Thunderstorm coverage is not expected to be widespread, but more scattered across the local area. Storm coverage may actually increase once the cold front passes with storms impacting areas south of Chicago and northwest Indiana. Strong winds and hail would be the primary concern if severe storms develop. Make sure you remain 'weather aware' during the day Monday with the risk for severe weather. We'll continue to keep you updated throughout the day.