Heat Wave Persists Over the Central U.S.; Significant Flooding Expected in the Northern Mid-Atlantic Tuesday

Dangerous and extreme heat will remain across portions of the Central U.S. this week, persisting across the Mid to Lower Mississippi Valleys, Gulf Coast, Southern Plains and portions of Texas. A heat wave over the Southwest will intensify late this week. Severe thunderstorms and flash flooding will spread from the Great Lakes/Ohio Valley to the Mid-Atlantic and Northeast the next few days. Read More >

Hazardous Weather Conditions

Current conditions at

Sherman/Denison, Grayson County Airport (KGYI)

Lat: 33.72°NLon: 96.67°WElev: 748ft.

Fair

95°F

35°C

Humidity 41%
Wind Speed SE 10 mph
Barometer 29.84 in
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Heat Index100°F (38°C)
Last update 27 Jul 7:35 pm CDT
Extended Forecast for

Denison TX

Heat Advisory July 27, 07:52pm until July 28, 08:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory July 27, 07:52pm until July 28, 08:00pm

    NOW until 8:00pm Tue

    Heat Advisory

  • Tonight

    Low: 80 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny and hot, with a high near 102. Heat index values as high as 109. South southwest wind 5 to 10 mph.

    High: 102 °F

    Hot

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 80. South wind around 5 mph.

    Low: 80 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny and hot, with a high near 102. Heat index values as high as 109. South southwest wind around 5 mph.

    High: 102 °F

    Hot

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 80. South southeast wind around 5 mph.

    Low: 80 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny and hot, with a high near 101. South wind 5 to 10 mph.

    High: 101 °F

    Hot

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 80. South southeast wind around 5 mph.

    Low: 80 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny and hot, with a high near 102. Southwest wind 5 to 10 mph.

    High: 102 °F

    Hot

Detailed Forecast

Tonight
Mostly clear, with a low around 80. South wind around 5 mph.
Tuesday
Sunny and hot, with a high near 102. Heat index values as high as 109. South southwest wind 5 to 10 mph.
Tuesday Night
Mostly clear, with a low around 80. South wind around 5 mph.
Wednesday
Mostly sunny and hot, with a high near 102. Heat index values as high as 109. South southwest wind around 5 mph.
Wednesday Night
Partly cloudy, with a low around 80. South southeast wind around 5 mph.
Thursday
Mostly sunny and hot, with a high near 101. South wind 5 to 10 mph.
Thursday Night
Partly cloudy, with a low around 80. South southeast wind around 5 mph.
Friday
Mostly sunny and hot, with a high near 102. Southwest wind 5 to 10 mph.
Friday Night
Partly cloudy, with a low around 80. South southwest wind 5 to 10 mph.
Saturday
Sunny, with a high near 98.
Saturday Night
Mostly clear, with a low around 75.
Sunday
Sunny, with a high near 95.
Sunday Night
Clear, with a low around 75.
Monday
Sunny, with a high near 97.
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ABOUT THIS FORECAST

 
Point Forecast:
Denison TX
 33.75°N 96.55°W (Elev. 758 ft)
6:12 pm CDT Jul 27, 2026
7pm CDT Jul 27, 2026-6pm CDT Aug 3, 2026
 
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Additional Resources

Radar & Satellite Image

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Hourly Weather Forecast

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