Tracking storms through tonight

 With heat and humidity sticking around another day, severe thunderstorm chances are elevated as well as a cold front moves through the region bringing strong to severe thunderstorm chances.

Currently the Storm Prediction Center has all of Northern Illinois and Southern Wisconsin under a slight risk for severe thunderstorms later this evening. The main hazards for this evening's round of thunderstorms will be damaging winds as most of the storms along the cold front will be in a line. However, lower risk hazards do include hail and a brief isolated tornado cannot be ruled out.

Tracking this risk out, storms begin in Northern Iowa along the cold front in the afternoon and begin to move east throughout the late afternoon and early evening. These storms will interact with an unstable airmass ahead of them helping create more storms and the damaging wind potential. As well some isolated showers will impact the region during the late afternoon before the main round arrives.

Moving into the 6 o'clock hour the cold front storms begin to move into Northwest Illinois as well as more storms ahead of the main line. Both isolated thunderstorms ahead of the line and storms along the line may be strong too severe with the previously mentioned hazards being the main threat. During the early evening hours, it will be most important to stay alert for watches and warnings as severe weather may approach quickly.

Near the 8 o'clock hour most of the region will be receiving precipitation and thunderstorms as the cold front continues to move east. Severe thunderstorm chances will be highest at this time and depending on storm evolution, this will determine main hazard type however with a line segment most likely damaging winds will be the main threat.

As the night continues the cold front will move through around midnight. At this time and times prior, instability will run out as the sun goes down. This will cause thunderstorms to weaken the farther east they push. By the midnight hour thunderstorms will move out of the region and with the cold front passage temperatures will begin to fall.

With the cold frontal passage tonight, this will bring cooler and more comfortable temperatures tomorrow after a night of active weather.