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.

A Few Clouds

46°F

8°C

Humidity 89%
Wind Speed W 9 mph
Barometer 29.75 in (1007.3 mb)
Dewpoint 43°F (6°C)
Visibility 10.00 mi
Wind Chill41°F (5°C)
Last update 14 Jan 2:53 am CST
Extended Forecast for

Collinsville IL

  • Overnight

    Overnight: Mostly cloudy, with a low around 38. West wind 8 to 11 mph, with gusts as high as 26 mph.

    Low: 38 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Cloudy through mid morning, then gradual clearing, with a temperature falling to around 30 by 5pm. Breezy, with a northwest wind 14 to 22 mph, with gusts as high as 37 mph.

    High: 39 °F⇓

    Gradual
    Clearing and
    Breezy

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 18. Northwest wind 8 to 16 mph, with gusts as high as 28 mph.

    Low: 18 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 33. Northwest wind around 7 mph becoming south in the afternoon.

    High: 33 °F

    Sunny

  • Thursday Night

    Thursday Night: A 30 percent chance of snow, mainly before midnight. Mostly cloudy, with a low around 27. South wind 6 to 13 mph becoming west after midnight. Winds could gust as high as 20 mph.

    Low: 27 °F

    Chance Snow

  • Friday

    Friday: Partly sunny, with a high near 44.

    High: 44 °F

    Partly Sunny

  • Friday Night

    Friday Night: A 20 percent chance of snow before midnight. Mostly cloudy, with a low around 20.

    Low: 20 °F

    Slight Chance
    Snow then
    Mostly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 27.

    High: 27 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 10.

    Low: 10 °F

    Partly Cloudy

Detailed Forecast

Overnight
Mostly cloudy, with a low around 38. West wind 8 to 11 mph, with gusts as high as 26 mph.
Wednesday
Cloudy through mid morning, then gradual clearing, with a temperature falling to around 30 by 5pm. Breezy, with a northwest wind 14 to 22 mph, with gusts as high as 37 mph.
Wednesday Night
Mostly clear, with a low around 18. Northwest wind 8 to 16 mph, with gusts as high as 28 mph.
Thursday
Sunny, with a high near 33. Northwest wind around 7 mph becoming south in the afternoon.
Thursday Night
A 30 percent chance of snow, mainly before midnight. Mostly cloudy, with a low around 27. South wind 6 to 13 mph becoming west after midnight. Winds could gust as high as 20 mph.
Friday
Partly sunny, with a high near 44.
Friday Night
A 20 percent chance of snow before midnight. Mostly cloudy, with a low around 20.
Saturday
Partly sunny, with a high near 27.
Saturday Night
Partly cloudy, with a low around 10.
Sunday
Mostly sunny, with a high near 26.
Sunday Night
Partly cloudy, with a low around 16.
M.L.King Day
Mostly sunny, with a high near 31.
Monday Night
Mostly clear, with a low around 13.
Tuesday
Sunny, with a high near 35.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Collinsville IL
 38.68°N 89.97°W (Elev. 502 ft)
Last Update:
3:16 am CST Jan 14, 2026
Forecast Valid:
3am CST Jan 14, 2026-6pm CST Jan 20, 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