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Severe Thunderstorms and Locally Heavy Rain Today

Severe thunderstorms and locally heavy rain are possible today from the southern plains to the Ohio valley and Mid-Atlantic. Elsewhere, hot temperatures are expected to persist for the interior Pacific Northwest. Elevated to critical fire weather conditions will occur in northeast Montana. Read More >

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Mostly Cloudy

76°F

24°C

Humidity 62%
Wind Speed W 12 G 21 mph
Barometer 29.84 in (1010.3 mb)
Dewpoint 62°F (17°C)
Visibility 10.00 mi
Heat Index78°F (26°C)
Last update 28 May 2:53 pm CDT
Extended Forecast for

O'Fallon IL

  • This
    Afternoon

    This Afternoon: Isolated showers before 4pm.  Mostly sunny, with a high near 79. West wind around 10 mph.  Chance of precipitation is 20%.

    Isolated
    Showers

    High: 79 °F

  • Tonight

    Tonight: Mostly clear, with a low around 57. West wind 3 to 8 mph.

    Mostly Clear

    Low: 57 °F

  • Memorial
    Day

    Memorial Day: A 20 percent chance of showers and thunderstorms after 2pm.  Sunny, with a high near 82. Light west wind increasing to 5 to 9 mph in the morning.

    Sunny then
    Slight Chance
    T-storms

    High: 82 °F

  • Monday
    Night

    Monday Night: A 20 percent chance of showers before 1am.  Partly cloudy, with a low around 56. Northwest wind 3 to 8 mph.

    Slight Chance
    Showers

    Low: 56 °F

  • Tuesday

    Tuesday: Sunny, with a high near 78. West wind 3 to 8 mph.

    Sunny

    High: 78 °F

  • Tuesday
    Night

    Tuesday Night: A 20 percent chance of showers.  Partly cloudy, with a low around 57.

    Slight Chance
    Showers

    Low: 57 °F

  • Wednesday

    Wednesday: Mostly sunny, with a high near 79.

    Mostly Sunny

    High: 79 °F

  • Wednesday
    Night

    Wednesday Night: Mostly clear, with a low around 58.

    Mostly Clear

    Low: 58 °F

  • Thursday

    Thursday: A 30 percent chance of showers and thunderstorms.  Partly sunny, with a high near 83.

    Chance
    Showers then
    Chance
    T-storms

    High: 83 °F

Detailed Forecast

This Afternoon
Isolated showers before 4pm. Mostly sunny, with a high near 79. West wind around 10 mph. Chance of precipitation is 20%.
Tonight
Mostly clear, with a low around 57. West wind 3 to 8 mph.
Memorial Day
A 20 percent chance of showers and thunderstorms after 2pm. Sunny, with a high near 82. Light west wind increasing to 5 to 9 mph in the morning.
Monday Night
A 20 percent chance of showers before 1am. Partly cloudy, with a low around 56. Northwest wind 3 to 8 mph.
Tuesday
Sunny, with a high near 78. West wind 3 to 8 mph.
Tuesday Night
A 20 percent chance of showers. Partly cloudy, with a low around 57.
Wednesday
Mostly sunny, with a high near 79.
Wednesday Night
Mostly clear, with a low around 58.
Thursday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 83.
Thursday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 64.
Friday
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 82.
Friday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 64.
Saturday
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 80.
Saturday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 62.
Sunday
A 20 percent chance of showers. Partly sunny, with a high near 76.
Click Map For Forecast
Point Forecast:
O'Fallon IL
 38.59°N 89.92°W (Elev. 551 ft)
3:28 pm CDT May 28, 2017
3pm CDT May 28, 2017-6pm CDT Jun 4, 2017
 
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