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NWS St. Louis Announces Changes To May 16, 2025 Tornado Damage Assessment

After a year-long review of new ground survey data and aerial imagery, NWS St. Louis made several adjustments to the May 16, 2025 tornado damage assessment. Read More >

Hazardous Weather Conditions

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair

64°F

18°C

Humidity 94%
Wind Speed S 14 mph
Barometer 29.96 in
Dewpoint 63°F (17°C)
Visibility 10.00 mi
Last update 18 May 9:50 pm CDT
Extended Forecast for

Bethalto IL

Flood Watch May 18, 10:18pm until May 19, 01:00pm
Click here for hazard details and duration
Flood Watch
  •  
    Flood Watch May 18, 10:18pm until May 19, 01:00pm

    NOW until 1:00pm Tue

    Flood Watch

  • Tonight

    Low: 64 °F

    Mostly Cloudy
    then Chance
    Showers

  • Tuesday

    Tuesday: Showers and thunderstorms likely, mainly after 5pm. Mostly cloudy, with a high near 81. South wind 11 to 15 mph becoming west in the afternoon. Winds could gust as high as 23 mph. Chance of precipitation is 60%.

    High: 81 °F

    T-storms
    Likely

  • Tuesday Night

    Tuesday Night: Showers and thunderstorms likely before 1am, then a chance of showers. Cloudy, with a low around 55. North wind 8 to 10 mph. Chance of precipitation is 60%.

    Low: 55 °F

    T-storms
    Likely

  • Wednesday

    Wednesday: Mostly cloudy, with a high near 68. North wind 9 to 11 mph.

    High: 68 °F

    Mostly Cloudy

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 49. Northeast wind around 9 mph.

    Low: 49 °F

    Mostly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 72.

    High: 72 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: A slight chance of showers, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 55. Chance of precipitation is 50%.

    Low: 55 °F

    Slight Chance
    Showers then
    Chance
    Showers

  • Friday

    Friday: Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 74. Chance of precipitation is 70%.

    High: 74 °F

    Showers
    Likely

Detailed Forecast

Tonight
A 30 percent chance of showers and thunderstorms, mainly after 4am. Mostly cloudy, with a low around 64. South wind 9 to 14 mph, with gusts as high as 24 mph.
Tuesday
Showers and thunderstorms likely, mainly after 5pm. Mostly cloudy, with a high near 81. South wind 11 to 15 mph becoming west in the afternoon. Winds could gust as high as 23 mph. Chance of precipitation is 60%.
Tuesday Night
Showers and thunderstorms likely before 1am, then a chance of showers. Cloudy, with a low around 55. North wind 8 to 10 mph. Chance of precipitation is 60%.
Wednesday
Mostly cloudy, with a high near 68. North wind 9 to 11 mph.
Wednesday Night
Mostly cloudy, with a low around 49. Northeast wind around 9 mph.
Thursday
Partly sunny, with a high near 72.
Thursday Night
A slight chance of showers, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 55. Chance of precipitation is 50%.
Friday
Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 74. Chance of precipitation is 70%.
Friday Night
A 40 percent chance of showers and thunderstorms, mainly before 1am. Mostly cloudy, with a low around 59.
Saturday
A slight chance of showers, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 79. Chance of precipitation is 30%.
Saturday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 60.
Sunday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 83.
Sunday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 63.
Memorial Day
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 85.
Basemap Options
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Bethalto IL
 38.9°N 90.05°W (Elev. 512 ft)
Last Update:
9:51 pm CDT May 18, 2026
Forecast Valid:
10pm CDT May 18, 2026-6pm CDT May 25, 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