DECATUR, IL. (WAND) - A strong high-pressure system will dominate the region this week, bringing dangerously hot and humid conditions to Central Illinois through Friday.
Temperatures will climb steadily throughout the week, with highs reaching into the low 90s by midweek. But the real story isn't just the thermometer — it's the heat index. As humidity climbs, feels-like temperatures could reach the upper 90s and low 100s Wednesday through Friday, creating dangerous conditions for outdoor activities.
Monday's Forecast
Monday will be a warm start to the week with highs in the upper 80s under sunny skies. Winds from the northeast at around 10 mph will help keep humidity levels more manageable. Overnight lows will drop to the upper 60s, providing some relief.
Tuesday: The Warmth Intensifies
Tuesday will be noticeably warmer with highs right around 90 degrees and continued sunshine. Humidity will begin to climb, pushing feels-like temperatures into the mid to upper 90s. Overnight lows will stay around 70 degrees.
Wednesday Through Friday: Dangerous Heat
The peak of the heat arrives Wednesday through Friday. High temperatures will settle in the low 90s, but the combination of heat and humidity will be the main concern. Heat index values will climb into the upper 90s and low 100s — potentially dangerous for those spending extended time outdoors. Sunny skies will persist throughout this period. Overnight lows will remain in the low 70s, providing minimal relief from the heat.
Weekend and Beyond
Rain chances will remain slim through the weekend as the high-pressure system slowly moves away. More importantly, cooler temperatures in the mid-80s will return early next week, finally breaking the heat and humidity.
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