Heavy Rain in the Appalachians and Central Gulf Coast; Heat Continues in the West; Monitoring the Tropics

Heavy to excessive rainfall over the southern Appalachians and portions of the central Gulf Coast may bring areas of flooding today. Hot temperatures are in place through today across much of the western U.S. and New England. Tropical Storm Erin is forecast to become a Major Hurricane this weekend as it moves across the central Atlantic Ocean. Monitor future forecasts for any East Coast impacts. Read More >

Current conditions at

Chamberlain, Chamberlain Municipal Airport (K9V9)

Lat: 43.77°NLon: 99.32°WElev: 1693ft.

Fair

58°F

14°C

Humidity 100%
Wind Speed Calm
Barometer 30.04 in
Dewpoint 58°F (14°C)
Visibility 10.00 mi
Last update 12 Aug 7:15 am CDT
Extended Forecast for

Gann Valley SD

  • Today

    Today: Sunny, with a high near 81. North northwest wind 8 to 11 mph, with gusts as high as 20 mph.

    High: 81 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 60. North wind around 7 mph becoming southeast after midnight.

    Low: 60 °F

    Mostly Clear

  • Wednesday

    Wednesday: A slight chance of showers and thunderstorms after 1pm.  Mostly sunny, with a high near 89. Breezy, with a south southeast wind 8 to 13 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 28 mph.  Chance of precipitation is 20%.

    High: 89 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms and
    Breezy

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms.  Mostly cloudy, with a low around 65. South southeast wind 14 to 18 mph, with gusts as high as 26 mph.  Chance of precipitation is 50%.

    Low: 65 °F

    Chance
    T-storms

  • Thursday

    Thursday: A slight chance of thunderstorms before 7am.  Sunny and hot, with a high near 92. South wind around 14 mph, with gusts as high as 22 mph.  Chance of precipitation is 10%.

    High: 92 °F

    Slight Chance
    T-storms then
    Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 68. Southeast wind 8 to 10 mph.

    Low: 68 °F

    Partly Cloudy

  • Friday

    Friday: Partly sunny, with a high near 89. East northeast wind 9 to 14 mph.

    High: 89 °F

    Partly Sunny

  • Friday Night

    Friday Night: A chance of showers and thunderstorms before 1am.  Mostly cloudy, with a low around 66. East wind 10 to 14 mph.  Chance of precipitation is 30%.

    Low: 66 °F

    Chance
    T-storms

  • Saturday

    Saturday: Partly sunny, with a high near 88. East wind 9 to 14 mph.

    High: 88 °F

    Partly Sunny

Detailed Forecast

Today
Sunny, with a high near 81. North northwest wind 8 to 11 mph, with gusts as high as 20 mph.
Tonight
Mostly clear, with a low around 60. North wind around 7 mph becoming southeast after midnight.
Wednesday
A slight chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 89. Breezy, with a south southeast wind 8 to 13 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 28 mph. Chance of precipitation is 20%.
Wednesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 65. South southeast wind 14 to 18 mph, with gusts as high as 26 mph. Chance of precipitation is 50%.
Thursday
A slight chance of thunderstorms before 7am. Sunny and hot, with a high near 92. South wind around 14 mph, with gusts as high as 22 mph. Chance of precipitation is 10%.
Thursday Night
Partly cloudy, with a low around 68. Southeast wind 8 to 10 mph.
Friday
Partly sunny, with a high near 89. East northeast wind 9 to 14 mph.
Friday Night
A chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 66. East wind 10 to 14 mph. Chance of precipitation is 30%.
Saturday
Partly sunny, with a high near 88. East wind 9 to 14 mph.
Saturday Night
A slight chance of showers and thunderstorms. Mostly cloudy, with a low around 66. Chance of precipitation is 20%.
Sunday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 86. Chance of precipitation is 20%.
Sunday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 65. Chance of precipitation is 30%.
Monday
Mostly sunny, with a high near 86.
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ABOUT THIS FORECAST

 
Point Forecast:
Gann Valley SD
 44.04°N 98.98°W (Elev. 1709 ft)
6:45 am CDT Aug 12, 2025
7am CDT Aug 12, 2025-6pm CDT Aug 18, 2025
 
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Additional Resources

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