Springfield, Ill. – Central Illinois will continue to enjoy below-normal temperatures through the end of the workweek before a significant warmup brings back summer heat and triple-digit heat index values by the end of the weekend.
According to the National Weather Service in Lincoln, afternoon highs will reach 77 to 79 degrees today and 76 to 78 degrees Friday, with dry weather expected for most of the region. A few isolated showers are possible Friday, mainly across western and central Illinois, but rain chances remain below 20% for many communities.
The weather pattern begins to change Saturday as temperatures climb into the lower to middle 80s. Shower and thunderstorm chances increase, especially across southern and southeastern Illinois, where rain probabilities rise to around 50% during the afternoon and evening.
By Sunday, much hotter air spreads across central Illinois, pushing highs into the upper 80s to lower 90s. Combined with increasing humidity, heat index values between 100 and 105 degrees are expected during the afternoon. The heat intensifies Monday, with highs reaching 91 to 97 degrees and heat index values once again near 105 degrees.
The return of dangerous heat will increase the risk of heat-related illnesses, especially for those spending extended time outdoors. Residents should drink plenty of water, wear lightweight clothing, limit strenuous afternoon activities and check on older adults, young children and anyone without reliable air conditioning.
Five-Day Forecast for Springfield, Illinois
- Thursday: High 77–79°, sunny and dry.
- Friday: High 76–78°, mostly cloudy with a slight chance of showers.
- Saturday: High 81–86°, scattered showers and thunderstorms possible, especially south and southeast.
- Sunday: High 88–93°, mostly sunny with a 100–105° heat index.
- Monday: High 91–97°, hot and humid with a heat index around 105°.
