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Severe Thunderstorms and Heavy Rain in Upper Midwest

A slow moving frontal boundary from the central Pains to the Upper Midwest will bring a potential for severe thunderstorms and heavy rain. Rain amounts of 1-3 inches, with locally heavier amounts can be expected. The threat of severe weather moves into the Ohio Valley and Northeast on Tuesday. Monsoon moisture continues to bring the threat of flash flooding to the Southwest and southern Rockies. Read More >

Hazardous Weather Conditions

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

87°F

31°C

Humidity 65%
Wind Speed W 5 mph
Barometer 30.09 in (1018.4 mb)
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Heat Index95°F (35°C)
Last update 21 Aug 9:53 am CDT
Extended Forecast for

Collinsville IL

  • Today

    Today: A 20 percent chance of showers and thunderstorms after 1pm.  Mostly sunny, with a high near 92. Heat index values as high as 101. Southwest wind 6 to 10 mph.

    Partly Sunny
    then Slight
    Chance
    T-storms

    High: 92 °F

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms, mainly after 5am.  Mostly cloudy, with a low around 73. South wind 7 to 9 mph.

    Partly Cloudy
    then Chance
    Showers

    Low: 73 °F

  • Tuesday

    Tuesday: A chance of showers and thunderstorms before 7am, then showers likely and possibly a thunderstorm between 7am and 10am, then a chance of showers and thunderstorms after 10am.  Mostly cloudy, with a high near 83. West wind 5 to 8 mph.  Chance of precipitation is 60%.

    Showers
    Likely then
    Chance
    T-storms

    High: 83 °F

  • Tuesday
    Night

    Tuesday Night: Mostly cloudy, then gradually becoming mostly clear, with a low around 60. North wind around 6 mph.

    Decreasing
    Clouds

    Low: 60 °F

  • Wednesday

    Wednesday: Sunny, with a high near 81. North wind 5 to 7 mph.

    Sunny

    High: 81 °F

  • Wednesday
    Night

    Wednesday Night: Mostly clear, with a low around 57.

    Mostly Clear

    Low: 57 °F

  • Thursday

    Thursday: Sunny, with a high near 81.

    Sunny

    High: 81 °F

  • Thursday
    Night

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

    Mostly Clear

    Low: 58 °F

  • Friday

    Friday: Mostly sunny, with a high near 80.

    Mostly Sunny

    High: 80 °F

Detailed Forecast

Today
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 92. Heat index values as high as 101. Southwest wind 6 to 10 mph.
Tonight
A 30 percent chance of showers and thunderstorms, mainly after 5am. Mostly cloudy, with a low around 73. South wind 7 to 9 mph.
Tuesday
A chance of showers and thunderstorms before 7am, then showers likely and possibly a thunderstorm between 7am and 10am, then a chance of showers and thunderstorms after 10am. Mostly cloudy, with a high near 83. West wind 5 to 8 mph. Chance of precipitation is 60%.
Tuesday Night
Mostly cloudy, then gradually becoming mostly clear, with a low around 60. North wind around 6 mph.
Wednesday
Sunny, with a high near 81. North wind 5 to 7 mph.
Wednesday Night
Mostly clear, with a low around 57.
Thursday
Sunny, with a high near 81.
Thursday Night
Mostly clear, with a low around 58.
Friday
Mostly sunny, with a high near 80.
Friday Night
Partly cloudy, with a low around 59.
Saturday
Mostly sunny, with a high near 82.
Saturday Night
Partly cloudy, with a low around 61.
Sunday
Mostly sunny, with a high near 83.
Click Map For Forecast
Point Forecast:
Collinsville IL
 38.68°N 90°W (Elev. 499 ft)
4:27 am CDT Aug 21, 2017
10am CDT Aug 21, 2017-6pm CDT Aug 27, 2017
 
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