Temperatures for both Saturday and Sunday warmed into the 80s, reaching 80 degrees on Saturday and 85 degrees on Sunday – the first 80 degree weekend this Spring season. The summer-like pattern will continue for the next several days, with highs reaching the low to mid 80s through Wednesday or Thursday. The muggy feeling will also stick around, pushing the heat index likely close to 90 degrees once again Memorial Day.
The next several days will feature many dry hours, but the storm chance increases as we head further into the week. Several upper level disturbances Sunday afternoon and evening allowed thunderstorms to quickly develop over southern Illinois, Missouri and Iowa. While most of this activity will weaken, and likely fade, before reaching northern Illinois and southern Wisconsin an isolated thunderstorm or two will be possible early Monday morning. Severe weather is not expected. Isolated thunderstorms will be possible during the day Monday as temperatures warm back into the mid 80s.
A better chance for thunderstorms will take place Tuesday and Wednesday as the strong ridge of high pressure over the eastern half of the country shifts further to the east and a cold front slides closer to the Stateline. The threat for any severe weather remains low, but thunderstorms will likely have heavy rainfall as moisture in the atmosphere remains rather high. Thursday should be our last chance for rain/thunder for the upcoming week as high pressure is set to follow the passage of a cold front Thursday night. This will lead to cool, easterly flow through at least the start of the weekend with temperatures warming into the mid 70s.