National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

76°F

24°C

Humidity 97%
Wind Speed Calm
Barometer 30.00 in (1015.5 mb)
Dewpoint 75°F (24°C)
Visibility 8.00 mi
Heat Index75°F (24°C)
Last update 18 Aug 1:53 am CDT
Extended Forecast for

3 Miles ESE Collinsville IL

Heat Advisory August 18, 02:18am until August 18, 08:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory August 18, 02:18am until August 18, 08:00pm

    NOW until 8:00pm Mon

    Heat Advisory

  • Overnight

    Low: 78 °F

    Partly Cloudy

  • Monday

    Monday: Sunny, with a high near 94. Heat index values as high as 107. South wind 3 to 7 mph.

    High: 94 °F

    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 74. South wind 3 to 5 mph.

    Low: 74 °F

    Partly Cloudy

  • Tuesday

    Tuesday: A 40 percent chance of showers and thunderstorms, mainly after 7am. Mostly sunny, with a high near 93. Heat index values as high as 105. Calm wind becoming west around 6 mph in the morning.

    High: 93 °F

    Chance
    Showers then
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 74. Light north wind.

    Low: 74 °F

    Chance
    T-storms

  • Wednesday

    Wednesday: A 30 percent chance of showers and thunderstorms, mainly after 1pm. Mostly sunny, with a high near 88.

    High: 88 °F

    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 66.

    Low: 66 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 86.

    High: 86 °F

    Mostly Sunny

Detailed Forecast

Overnight
Partly cloudy, with a low around 78. Light southeast wind.
Monday
Sunny, with a high near 94. Heat index values as high as 107. South wind 3 to 7 mph.
Monday Night
Partly cloudy, with a low around 74. South wind 3 to 5 mph.
Tuesday
A 40 percent chance of showers and thunderstorms, mainly after 7am. Mostly sunny, with a high near 93. Heat index values as high as 105. Calm wind becoming west around 6 mph in the morning.
Tuesday Night
A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 74. Light north wind.
Wednesday
A 30 percent chance of showers and thunderstorms, mainly after 1pm. Mostly sunny, with a high near 88.
Wednesday Night
Partly cloudy, with a low around 66.
Thursday
Mostly sunny, with a high near 86.
Thursday Night
Mostly clear, with a low around 65.
Friday
Sunny, with a high near 87.
Friday Night
Mostly clear, with a low around 66.
Saturday
Mostly sunny, with a high near 87.
Saturday Night
Mostly clear, with a low around 62.
Sunday
Sunny, with a high near 82.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
3 Miles ESE Collinsville IL
 38.68°N 89.95°W (Elev. 548 ft)
Last Update:
2:16 am CDT Aug 18, 2025
Forecast Valid:
2am CDT Aug 18, 2025-6pm CDT Aug 24, 2025
 
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