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Severe Thunderstorms With Heavy Rain Possible In The Upper Midwest; Excessive Heat For Central U.S.

Several rounds of strong to severe thunderstorms will be possible from the northern Plains and upper Midwest to the Great Lakes through Friday. Damaging winds, large hail, and flooding will be the primary threats with these storms. Excessive heat will grip the central Plains with heat indices approaching 105 to 110 degrees. Very hot and humid conditions are likely to expand into the Mid Atlantic. Read More >

Current conditions at

Washington/Dulles International Airport, DC (KIAD)

Lat: 38.93°NLon: 77.45°WElev: 312ft.

Mostly Cloudy

93°F

34°C

Humidity 46%
Wind Speed SW 6 mph
Barometer 29.92 in (1012.7 mb)
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Heat Index98°F (37°C)
Last update 20 Jul 5:52 pm EDT
Extended Forecast for

Herndon VA

Heat Advisory until July 20, 07:00pm
Click here for hazard details and duration
...
  •  
    Heat Advisory until July 20, 07:00pm

    NOW until
    7:00pm Thu

    Heat Advisory

  • Tonight

    Tonight: A slight chance of showers after 2am.  Partly cloudy, with a low around 78. West wind 3 to 8 mph.  Chance of precipitation is 20%.

    Partly Cloudy
    then Slight
    Chance
    Showers

    Low: 78 °F

  • Friday

    Friday: A slight chance of showers and thunderstorms.  Mostly sunny and hot, with a high near 97. Heat index values as high as 104. Northwest wind 5 to 8 mph.  Chance of precipitation is 20%.

    Slight Chance
    T-storms

    High: 97 °F

  • Friday
    Night

    Friday Night: A chance of showers and thunderstorms, mainly before 2am.  Partly cloudy, with a low around 75. Northwest wind around 6 mph becoming calm  after midnight.  Chance of precipitation is 30%.

    Chance
    T-storms

    Low: 75 °F

  • Saturday

    Saturday: A chance of showers and thunderstorms, mainly after 8am.  Partly sunny, with a high near 93. Calm wind becoming southwest around 6 mph in the afternoon.  Chance of precipitation is 40%.

    Chance
    T-storms

    High: 93 °F

  • Saturday
    Night

    Saturday Night: A chance of showers and thunderstorms.  Mostly cloudy, with a low around 74. Southwest wind around 6 mph becoming calm  after midnight.  Chance of precipitation is 50%.

    Chance
    T-storms

    Low: 74 °F

  • Sunday

    Sunday: A chance of showers and thunderstorms.  Mostly cloudy, with a high near 93. Chance of precipitation is 50%.

    Chance
    T-storms

    High: 93 °F

  • Sunday
    Night

    Sunday Night: A chance of showers and thunderstorms.  Mostly cloudy, with a low around 74. Chance of precipitation is 30%.

    Chance
    T-storms

    Low: 74 °F

  • Monday

    Monday: A chance of showers and thunderstorms.  Partly sunny, with a high near 91. Chance of precipitation is 30%.

    Chance
    T-storms

    High: 91 °F

Detailed Forecast

Tonight
A slight chance of showers after 2am. Partly cloudy, with a low around 78. West wind 3 to 8 mph. Chance of precipitation is 20%.
Friday
A slight chance of showers and thunderstorms. Mostly sunny and hot, with a high near 97. Heat index values as high as 104. Northwest wind 5 to 8 mph. Chance of precipitation is 20%.
Friday Night
A chance of showers and thunderstorms, mainly before 2am. Partly cloudy, with a low around 75. Northwest wind around 6 mph becoming calm after midnight. Chance of precipitation is 30%.
Saturday
A chance of showers and thunderstorms, mainly after 8am. Partly sunny, with a high near 93. Calm wind becoming southwest around 6 mph in the afternoon. Chance of precipitation is 40%.
Saturday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 74. Southwest wind around 6 mph becoming calm after midnight. Chance of precipitation is 50%.
Sunday
A chance of showers and thunderstorms. Mostly cloudy, with a high near 93. Chance of precipitation is 50%.
Sunday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 74. Chance of precipitation is 30%.
Monday
A chance of showers and thunderstorms. Partly sunny, with a high near 91. Chance of precipitation is 30%.
Monday Night
Mostly cloudy, with a low around 70.
Tuesday
Mostly sunny, with a high near 84.
Tuesday Night
Partly cloudy, with a low around 66.
Wednesday
Mostly sunny, with a high near 85.
Wednesday Night
Partly cloudy, with a low around 67.
Thursday
A chance of showers and thunderstorms. Mostly sunny, with a high near 87. Chance of precipitation is 30%.
Click Map For Forecast
Point Forecast:
Herndon VA
 38.97°N 77.38°W (Elev. 354 ft)
4:27 pm EDT Jul 20, 2017
6pm EDT Jul 20, 2017-6pm EDT Jul 27, 2017
 
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