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Extreme Heat and Excessive Rainfall This Week

A significant heat wave continues for the Rockies, Northern Plains, and Great Lakes into the Mid-Atlantic, peaking in intensity through midweek and lingering across parts of the Northern Plains and Midwest until this weekend. Excessive rainfall my bring life-threatening and locally catastrophic flash and urban flooding across portions of southwestern Texas through early Friday. Read More >

Hazardous Weather Conditions

Current conditions at

University of Illinois - Willard (KCMI)

Lat: 40.03°NLon: 88.28°WElev: 741ft.

Fair

74°F

23°C

Humidity 88%
Wind Speed Calm
Barometer 30.15 in (1020.4 mb)
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Last update 14 Jul 10:53 pm CDT
Extended Forecast for

Monticello IL

  • Tonight

    Tonight: Mostly clear, with a low around 69. Calm wind.

    Low: 69 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 91. Heat index values as high as 100. Calm wind.

    High: 91 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Increasing clouds, with a low around 71. Calm wind.

    Low: 71 °F

    Increasing
    Clouds

  • Thursday

    Thursday: A chance of showers between 1pm and 4pm, then a chance of showers and thunderstorms after 4pm. Sunny, with a high near 90. Light south southeast wind. Chance of precipitation is 30%.

    High: 90 °F

    Mostly Sunny
    then Chance
    T-storms

  • Thursday Night

    Thursday Night: A chance of thunderstorms before 7pm. Mostly clear, with a low around 72. South wind 3 to 5 mph. Chance of precipitation is 30%.

    Low: 72 °F

    Chance
    T-storms then
    Mostly Clear

  • Friday

    Friday: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1pm. High near 88. West southwest wind 3 to 7 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

    High: 88 °F

    Chance
    T-storms then
    T-storms

  • Friday Night

    Friday Night: Partly cloudy, with a low around 71. Southwest wind 6 to 8 mph.

    Low: 71 °F

    Partly Cloudy

  • Saturday

    Saturday: Sunny, with a high near 89.

    High: 89 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 71.

    Low: 71 °F

    Mostly Clear

Detailed Forecast

Tonight
Mostly clear, with a low around 69. Calm wind.
Wednesday
Sunny, with a high near 91. Heat index values as high as 100. Calm wind.
Wednesday Night
Increasing clouds, with a low around 71. Calm wind.
Thursday
A chance of showers between 1pm and 4pm, then a chance of showers and thunderstorms after 4pm. Sunny, with a high near 90. Light south southeast wind. Chance of precipitation is 30%.
Thursday Night
A chance of thunderstorms before 7pm. Mostly clear, with a low around 72. South wind 3 to 5 mph. Chance of precipitation is 30%.
Friday
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1pm. High near 88. West southwest wind 3 to 7 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Friday Night
Partly cloudy, with a low around 71. Southwest wind 6 to 8 mph.
Saturday
Sunny, with a high near 89.
Saturday Night
Mostly clear, with a low around 71.
Sunday
Sunny, with a high near 88.
Sunday Night
Partly cloudy, with a low around 70.
Monday
Mostly sunny, with a high near 88.
Monday Night
Partly cloudy, with a low around 70.
Tuesday
Mostly sunny, with a high near 86.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Monticello IL
 40.03°N 88.58°W (Elev. 650 ft)
Last Update:
10:36 pm CDT Jul 14, 2026
Forecast Valid:
11pm CDT Jul 14, 2026-6pm CDT Jul 21, 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