Severe Thunderstorms and Heavy Rain in the Mid-Atlantic; Heat Persists Across the South

Scattered severe thunderstorms and excessive rainfall are possible into the night in the Mid Atlantic, and heavy rain will shift to Virginia and the Carolinas on Friday. Severe thunderstorms are also possible in the Central Plains into the Upper MS Valley and the Deep South tonight. Dangerous heat persists across the Southern Plains and Lower MS Valley and heat will expand into the Southwest. Read More >

Current conditions at

Sherman/Denison, Grayson County Airport (KGYI)

Lat: 33.72°NLon: 96.67°WElev: 748ft.

Fair

81°F

27°C

Humidity 59%
Wind Speed SW 5 mph
Barometer 30.00 in
Dewpoint 65°F (18°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 21 Aug 5:35 am CDT
Extended Forecast for

Dorchester TX

Extreme Heat Warning August 21, 05:43am until August 21, 08:00pm
Click here for hazard details and duration
Extreme Heat Warning
  •  
    Extreme Heat Warning August 21, 05:43am until August 21, 08:00pm

    NOW until 8:00pm Fri

    Extreme Heat Warning

  • Today

    High: 104 °F

    Sunny then
    Slight Chance
    T-storms

  • Tonight

    Tonight: A 20 percent chance of showers and thunderstorms before 1am.  Increasing clouds, with a low around 79. South wind around 5 mph.

    Low: 79 °F

    Slight Chance
    T-storms

  • Saturday

    Saturday: Mostly sunny and hot, with a high near 104. Heat index values as high as 108. Southeast wind around 5 mph becoming south southwest in the morning.

    High: 104 °F

    Hot

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 78. South wind 5 to 10 mph.

    Low: 78 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny and hot, with a high near 103. South southwest wind around 5 mph.

    High: 103 °F

    Hot

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 80. South wind 5 to 10 mph.

    Low: 80 °F

    Partly Cloudy

  • Monday

    Monday: Sunny and hot, with a high near 103. South southwest wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 103 °F

    Hot

  • Monday Night

    Monday Night: Mostly clear, with a low around 81. South wind around 15 mph, with gusts as high as 20 mph.

    Low: 81 °F

    Mostly Clear

Detailed Forecast

Today
A 10 percent chance of showers and thunderstorms after 4pm. Sunny and hot, with a high near 104. South southwest wind around 5 mph.
Tonight
A 20 percent chance of showers and thunderstorms before 1am. Increasing clouds, with a low around 79. South wind around 5 mph.
Saturday
Mostly sunny and hot, with a high near 104. Heat index values as high as 108. Southeast wind around 5 mph becoming south southwest in the morning.
Saturday Night
Partly cloudy, with a low around 78. South wind 5 to 10 mph.
Sunday
Sunny and hot, with a high near 103. South southwest wind around 5 mph.
Sunday Night
Partly cloudy, with a low around 80. South wind 5 to 10 mph.
Monday
Sunny and hot, with a high near 103. South southwest wind 10 to 15 mph, with gusts as high as 20 mph.
Monday Night
Mostly clear, with a low around 81. South wind around 15 mph, with gusts as high as 20 mph.
Tuesday
Sunny and hot, with a high near 104. Southwest wind 10 to 15 mph, with gusts as high as 20 mph.
Tuesday Night
Mostly clear, with a low around 81.
Wednesday
A 20 percent chance of showers and thunderstorms. Sunny and hot, with a high near 101.
Wednesday Night
Mostly clear, with a low around 77.
Thursday
Sunny and hot, with a high near 99.
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ABOUT THIS FORECAST

 
Point Forecast:
Dorchester TX
 33.53°N 96.68°W (Elev. 840 ft)
1:26 am CDT Aug 21, 2026
5am CDT Aug 21, 2026-6pm CDT Aug 27, 2026
 
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Additional Resources

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