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

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Mostly Cloudy

46°F

8°C

Humidity 96%
Wind Speed N 3 mph
Barometer 30.08 in (1018.4 mb)
Dewpoint 45°F (7°C)
Visibility 7.00 mi
Last update 19 Nov 12:53 am CST
Extended Forecast for

Collinsville IL

  • Overnight

    Overnight: Cloudy, with a low around 46. North wind around 6 mph.

    Low: 46 °F

    Cloudy

  • Wednesday

    Wednesday: Cloudy, with a high near 58. North wind around 5 mph becoming calm in the morning.

    High: 58 °F

    Cloudy

  • Wednesday Night

    Wednesday Night: A 20 percent chance of rain after midnight. Mostly cloudy, with a low around 49. Light southeast wind.

    Low: 49 °F

    Mostly Cloudy
    then Slight
    Chance Rain

  • Thursday

    Thursday: Rain likely and possibly a thunderstorm before noon, then rain likely between noon and 3pm, then rain likely and possibly a thunderstorm after 3pm. Cloudy, with a high near 61. South wind 5 to 8 mph. Chance of precipitation is 70%.

    High: 61 °F

    Rain Likely

  • Thursday Night

    Thursday Night: Rain likely and possibly a thunderstorm. Cloudy, with a low around 54. Calm wind becoming north around 5 mph after midnight. Chance of precipitation is 70%.

    Low: 54 °F

    Rain Likely

  • Friday

    Friday: Rain. High near 60. Chance of precipitation is 80%.

    High: 60 °F

    Rain

  • Friday Night

    Friday Night: A chance of rain and thunderstorms before midnight, then a slight chance of rain. Mostly cloudy, with a low around 48. Chance of precipitation is 50%.

    Low: 48 °F

    Chance Rain
    then Slight
    Chance Rain

  • Saturday

    Saturday: Partly sunny, with a high near 59.

    High: 59 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 42.

    Low: 42 °F

    Mostly Clear

Detailed Forecast

Overnight
Cloudy, with a low around 46. North wind around 6 mph.
Wednesday
Cloudy, with a high near 58. North wind around 5 mph becoming calm in the morning.
Wednesday Night
A 20 percent chance of rain after midnight. Mostly cloudy, with a low around 49. Light southeast wind.
Thursday
Rain likely and possibly a thunderstorm before noon, then rain likely between noon and 3pm, then rain likely and possibly a thunderstorm after 3pm. Cloudy, with a high near 61. South wind 5 to 8 mph. Chance of precipitation is 70%.
Thursday Night
Rain likely and possibly a thunderstorm. Cloudy, with a low around 54. Calm wind becoming north around 5 mph after midnight. Chance of precipitation is 70%.
Friday
Rain. High near 60. Chance of precipitation is 80%.
Friday Night
A chance of rain and thunderstorms before midnight, then a slight chance of rain. Mostly cloudy, with a low around 48. Chance of precipitation is 50%.
Saturday
Partly sunny, with a high near 59.
Saturday Night
Mostly clear, with a low around 42.
Sunday
Sunny, with a high near 62.
Sunday Night
Partly cloudy, with a low around 44.
Monday
A 30 percent chance of rain. Partly sunny, with a high near 61.
Monday Night
A 40 percent chance of rain. Mostly cloudy, with a low around 46.
Tuesday
A 40 percent chance of rain. Mostly cloudy, with a high near 58.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Collinsville IL
 38.68°N 89.97°W (Elev. 502 ft)
Last Update:
12:41 am CST Nov 19, 2025
Forecast Valid:
1am CST Nov 19, 2025-6pm CST Nov 25, 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