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Excessive Rainfall Potential for the Southeast; Heat Expands for Center of the Nation; Critical Fire Weather for Pacific Northwest

Flash flooding threatens areas from the Tennessee Valley to the Carolinas as storms repeat along a stalled front. Monsoonal storms may trigger flooding in the Southwest. Dangerous heat expands across the Desert Southwest, Plains, mid-Mississippi Valley and Southern Tier. Critical fire weather for interior Pacific Northwest. Cooler, drier air brings brief relief to the Great Lakes and Northeast. Read More >

Hazardous Weather Conditions

Current conditions at

University of Illinois - Willard (KCMI)

Lat: 40.03°NLon: 88.28°WElev: 741ft.

Overcast

67°F

19°C

Humidity 91%
Wind Speed SW 3 mph
Barometer 30.09 in (1018.6 mb)
Dewpoint 64°F (18°C)
Visibility 10.00 mi
Last update 24 Jul 11:53 pm CDT
Extended Forecast for

Monticello IL

Heat Advisory July 26, 12:00pm until July 27, 09:00pm
Click here for hazard details and duration
Heat Advisory

  • Overnight

    Overnight: Mostly clear early, then becoming mostly cloudy, with a low around 64. Light south wind.

    Low: 64 °F

    Mostly Cloudy

  • Saturday

    Saturday: A slight chance of showers between 10am and 11am. Mostly cloudy, with a high near 82. South wind 5 to 9 mph. Chance of precipitation is 20%.

    High: 82 °F

    Slight Chance
    Showers then
    Mostly Cloudy

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 68. South wind around 6 mph becoming calm in the evening.

    Low: 68 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 91. Heat index values as high as 103. Calm wind becoming west southwest 5 to 7 mph in the afternoon.

    High: 91 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 73. Southwest wind 6 to 9 mph.

    Low: 73 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 92. Southwest wind 9 to 17 mph, with gusts as high as 25 mph.

    High: 92 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 74. Southwest wind 9 to 15 mph becoming northwest after midnight. Winds could gust as high as 21 mph.

    Low: 74 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 91.

    High: 91 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 68.

    Low: 68 °F

    Mostly Clear

Detailed Forecast

Overnight
Mostly clear early, then becoming mostly cloudy, with a low around 64. Light south wind.
Saturday
A slight chance of showers between 10am and 11am. Mostly cloudy, with a high near 82. South wind 5 to 9 mph. Chance of precipitation is 20%.
Saturday Night
Partly cloudy, with a low around 68. South wind around 6 mph becoming calm in the evening.
Sunday
Mostly sunny, with a high near 91. Heat index values as high as 103. Calm wind becoming west southwest 5 to 7 mph in the afternoon.
Sunday Night
Partly cloudy, with a low around 73. Southwest wind 6 to 9 mph.
Monday
Mostly sunny, with a high near 92. Southwest wind 9 to 17 mph, with gusts as high as 25 mph.
Monday Night
Mostly clear, with a low around 74. Southwest wind 9 to 15 mph becoming northwest after midnight. Winds could gust as high as 21 mph.
Tuesday
Sunny, with a high near 91.
Tuesday Night
Mostly clear, with a low around 68.
Wednesday
Sunny, with a high near 89.
Wednesday Night
Mostly clear, with a low around 67.
Thursday
Mostly sunny, with a high near 88.
Thursday Night
Mostly clear, with a low around 68.
Friday
Mostly sunny, with a high near 88.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Monticello IL
 40.05°N 88.58°W (Elev. 650 ft)
Last Update:
11:36 pm CDT Jul 24, 2026
Forecast Valid:
12am CDT Jul 25, 2026-6pm CDT Jul 31, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation