National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Extreme Heat in the Southwest; Severe Weather in the Northern Plains; Heavy Rain in the East

Extreme heat continues across the Southwest as temperatures may top 120 degrees. The heat may expand across the West and south-central U.S. into the middle of the month. Severe thunderstorms capable of severe wind gusts and large hail will be the primary hazards today across the northern Plains into the upper Midwest. Rainfall could be locally heavy across the Eastern U.S. today. Read More >

Hazardous Weather Conditions

Current conditions at

Washington/Dulles International Airport, DC (KIAD)

Lat: 38.93°NLon: 77.45°WElev: 312ft.

Mostly Cloudy

86°F

30°C

Humidity 61%
Wind Speed NW 10 mph
Barometer 29.83 in (1009.6 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Heat Index91°F (33°C)
Last update 3 Aug 12:52 pm EDT
Extended Forecast for

Herndon VA

  • This Afternoon

    This Afternoon: A chance of showers and thunderstorms. Mostly sunny, with a high near 85. Northwest wind around 7 mph. Chance of precipitation is 30%.

    High: 85 °F

    Chance
    T-storms

  • Tonight

    Tonight: Increasing clouds, with a low around 67. North wind 3 to 5 mph.

    Low: 67 °F

    Increasing
    Clouds

  • Tuesday

    Tuesday: Partly sunny, with a high near 85. Northeast wind around 6 mph.

    High: 85 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: A chance of showers and thunderstorms after 2am. Mostly cloudy, with a low around 68. East wind around 5 mph becoming calm in the evening. Chance of precipitation is 40%.

    Low: 68 °F

    Mostly Cloudy
    then Chance
    Showers

  • Wednesday

    Wednesday: A chance of showers and thunderstorms before 8am, then a slight chance of showers between 8am and 2pm, then showers likely and possibly a thunderstorm after 2pm. Partly sunny, with a high near 87. Calm wind becoming south 5 to 7 mph in the afternoon. Chance of precipitation is 60%.

    High: 87 °F

    Chance
    Showers then
    Showers
    Likely

  • Wednesday Night

    Wednesday Night: Showers likely and possibly a thunderstorm before 8pm. Mostly cloudy, with a low around 72. Chance of precipitation is 60%.

    Low: 72 °F

    Showers
    Likely then
    Partly Cloudy

  • Thursday

    Thursday: A chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 90. Chance of precipitation is 40%.

    High: 90 °F

    Mostly Sunny
    then Chance
    T-storms

  • Thursday Night

    Thursday Night: A chance of showers and thunderstorms, mainly before 8pm. Partly cloudy, with a low around 73. Chance of precipitation is 30%.

    Low: 73 °F

    Chance
    T-storms

  • Friday

    Friday: A chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 90. Chance of precipitation is 40%.

    High: 90 °F

    Mostly Sunny
    then Chance
    T-storms

Detailed Forecast

This Afternoon
A chance of showers and thunderstorms. Mostly sunny, with a high near 85. Northwest wind around 7 mph. Chance of precipitation is 30%.
Tonight
Increasing clouds, with a low around 67. North wind 3 to 5 mph.
Tuesday
Partly sunny, with a high near 85. Northeast wind around 6 mph.
Tuesday Night
A chance of showers and thunderstorms after 2am. Mostly cloudy, with a low around 68. East wind around 5 mph becoming calm in the evening. Chance of precipitation is 40%.
Wednesday
A chance of showers and thunderstorms before 8am, then a slight chance of showers between 8am and 2pm, then showers likely and possibly a thunderstorm after 2pm. Partly sunny, with a high near 87. Calm wind becoming south 5 to 7 mph in the afternoon. Chance of precipitation is 60%.
Wednesday Night
Showers likely and possibly a thunderstorm before 8pm. Mostly cloudy, with a low around 72. Chance of precipitation is 60%.
Thursday
A chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 90. Chance of precipitation is 40%.
Thursday Night
A chance of showers and thunderstorms, mainly before 8pm. Partly cloudy, with a low around 73. Chance of precipitation is 30%.
Friday
A chance of showers and thunderstorms after 2pm. Mostly sunny, with a high near 90. Chance of precipitation is 40%.
Friday Night
A chance of showers and thunderstorms before 2am. Mostly cloudy, with a low around 72. Chance of precipitation is 40%.
Saturday
Showers likely and possibly a thunderstorm. Mostly sunny, with a high near 89. Chance of precipitation is 60%.
Saturday Night
Showers and thunderstorms likely. Mostly cloudy, with a low around 71. Chance of precipitation is 60%.
Sunday
A chance of showers and thunderstorms. Mostly sunny, with a high near 89. Chance of precipitation is 40%.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Herndon VA
 38.97°N 77.41°W (Elev. 348 ft)
Last Update:
10:53 am EDT Aug 3, 2026
Forecast Valid:
1pm EDT Aug 3, 2026-6pm EDT Aug 9, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation