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

82°F

28°C

Humidity 63%
Wind Speed S 6 mph
Barometer 29.89 in (1011.6 mb)
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Heat Index85°F (29°C)
Last update 13 Oct 7:53 pm CDT
Extended Forecast for

Waterloo IL

  • Tonight

    Tonight: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 5am. Increasing clouds, with a low around 71. South wind 6 to 8 mph. Chance of precipitation is 60%.

    Low: 71 °F

    Clear then
    Showers
    Likely

  • Wednesday

    Wednesday: Showers and possibly a thunderstorm, mainly before 1pm, then a chance of showers and thunderstorms after 1pm. Patchy fog between 1pm and 2pm. High near 78. West wind around 5 mph becoming light and variable. Chance of precipitation is 90%.

    High: 78 °F

    Showers and
    Patchy Fog
    then Showers
    Likely and
    Patchy Fog

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 3am. Mostly cloudy, with a low around 67. East wind around 6 mph. Chance of precipitation is 70%.

    Low: 67 °F

    Slight Chance
    T-storms then
    Showers
    Likely

  • Thursday

    Thursday: Showers and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms between 1pm and 4pm, then showers likely and possibly a thunderstorm after 4pm. High near 84. Light and variable wind becoming southwest 5 to 9 mph in the morning. Chance of precipitation is 90%.

    High: 84 °F

    Showers

  • Thursday Night

    Thursday Night: Showers likely and possibly a thunderstorm before 7pm, then a chance of showers and thunderstorms between 7pm and 1am, then a slight chance of showers after 1am. Mostly cloudy, with a low around 50. West wind 6 to 16 mph becoming northwest after midnight. Winds could gust as high as 28 mph. Chance of precipitation is 60%.

    Low: 50 °F

    Showers
    Likely

  • Friday

    Friday: Mostly sunny, with a high near 60. Breezy.

    High: 60 °F

    Mostly Sunny
    then Sunny
    and Breezy

  • Friday Night

    Friday Night: Mostly clear, with a low around 38.

    Low: 38 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 61.

    High: 61 °F

    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 38.

    Low: 38 °F

    Clear

Detailed Forecast

Tonight
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 5am. Increasing clouds, with a low around 71. South wind 6 to 8 mph. Chance of precipitation is 60%.
Wednesday
Showers and possibly a thunderstorm, mainly before 1pm, then a chance of showers and thunderstorms after 1pm. Patchy fog between 1pm and 2pm. High near 78. West wind around 5 mph becoming light and variable. Chance of precipitation is 90%.
Wednesday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 3am. Mostly cloudy, with a low around 67. East wind around 6 mph. Chance of precipitation is 70%.
Thursday
Showers and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms between 1pm and 4pm, then showers likely and possibly a thunderstorm after 4pm. High near 84. Light and variable wind becoming southwest 5 to 9 mph in the morning. Chance of precipitation is 90%.
Thursday Night
Showers likely and possibly a thunderstorm before 7pm, then a chance of showers and thunderstorms between 7pm and 1am, then a slight chance of showers after 1am. Mostly cloudy, with a low around 50. West wind 6 to 16 mph becoming northwest after midnight. Winds could gust as high as 28 mph. Chance of precipitation is 60%.
Friday
Mostly sunny, with a high near 60. Breezy.
Friday Night
Mostly clear, with a low around 38.
Saturday
Sunny, with a high near 61.
Saturday Night
Clear, with a low around 38.
Sunday
Sunny, with a high near 69.
Sunday Night
Partly cloudy, with a low around 46.
Monday
Mostly sunny, with a high near 73.
Monday Night
Partly cloudy, with a low around 49.
Tuesday
Mostly sunny, with a high near 78.
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ABOUT THIS FORECAST

 
Point Forecast:
Waterloo IL
 38.33°N 90.16°W (Elev. 600 ft)
Last Update:
6:01 pm CDT Oct 13, 2026
Forecast Valid:
8pm CDT Oct 13, 2026-6pm CDT Oct 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