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.

Fair

75°F

24°C

Humidity 84%
Wind Speed S 5 mph
Barometer 29.95 in (1013.6 mb)
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Last update 14 Oct 2:53 am CDT
Extended Forecast for

Granite City IL

  • Overnight

    Overnight: Showers and thunderstorms likely, mainly after 5am. Mostly cloudy, with a low around 72. West wind around 6 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.

    Low: 72 °F

    T-storms
    Likely

  • Wednesday

    Wednesday: Showers and thunderstorms before 11am, then showers likely and possibly a thunderstorm between 11am and 1pm, then a chance of showers and thunderstorms after 1pm. High near 80. West wind 5 to 7 mph becoming northeast in the morning. Chance of precipitation is 90%.

    High: 80 °F

    T-storms then
    Showers
    Likely

  • Wednesday Night

    Wednesday Night: A slight chance of showers, then a chance of showers and thunderstorms after 10pm. Mostly cloudy, with a low around 67. North wind around 6 mph becoming light and variable. Chance of precipitation is 30%.

    Low: 67 °F

    Chance
    Showers then
    Chance
    T-storms

  • Thursday

    Thursday: Showers and possibly a thunderstorm before noon, then a chance of showers and thunderstorms between noon and 5pm, then showers likely and possibly a thunderstorm after 5pm. High near 84. East wind 6 to 10 mph becoming southwest in the afternoon. Chance of precipitation is 80%.

    High: 84 °F

    Showers

  • Thursday Night

    Thursday Night: Showers and possibly a thunderstorm before 1am, then a chance of showers. Low around 49. Southwest wind 8 to 17 mph becoming northwest after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 80%.

    Low: 49 °F

    Showers

  • Friday

    Friday: Partly sunny, with a high near 62. Breezy.

    High: 62 °F

    Partly Sunny
    and Breezy

  • Friday Night

    Friday Night: Mostly clear, with a low around 39.

    Low: 39 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 64.

    High: 64 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 39.

    Low: 39 °F

    Clear

Detailed Forecast

Overnight
Showers and thunderstorms likely, mainly after 5am. Mostly cloudy, with a low around 72. West wind around 6 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.
Wednesday
Showers and thunderstorms before 11am, then showers likely and possibly a thunderstorm between 11am and 1pm, then a chance of showers and thunderstorms after 1pm. High near 80. West wind 5 to 7 mph becoming northeast in the morning. Chance of precipitation is 90%.
Wednesday Night
A slight chance of showers, then a chance of showers and thunderstorms after 10pm. Mostly cloudy, with a low around 67. North wind around 6 mph becoming light and variable. Chance of precipitation is 30%.
Thursday
Showers and possibly a thunderstorm before noon, then a chance of showers and thunderstorms between noon and 5pm, then showers likely and possibly a thunderstorm after 5pm. High near 84. East wind 6 to 10 mph becoming southwest in the afternoon. Chance of precipitation is 80%.
Thursday Night
Showers and possibly a thunderstorm before 1am, then a chance of showers. Low around 49. Southwest wind 8 to 17 mph becoming northwest after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 80%.
Friday
Partly sunny, with a high near 62. Breezy.
Friday Night
Mostly clear, with a low around 39.
Saturday
Sunny, with a high near 64.
Saturday Night
Clear, with a low around 39.
Sunday
Sunny, with a high near 71.
Sunday Night
Partly cloudy, with a low around 45.
Monday
Partly sunny, with a high near 74.
Monday Night
Partly cloudy, with a low around 48.
Tuesday
Mostly sunny, with a high near 79.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Granite City IL
 38.73°N 90.11°W (Elev. 417 ft)
Last Update:
1:26 am CDT Oct 14, 2026
Forecast Valid:
3am CDT Oct 14, 2026-6pm CDT Oct 20, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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