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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

92°F

33°C

Humidity 47%
Wind Speed S 10 mph
Barometer 29.95 in (1013.9 mb)
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Heat Index97°F (36°C)
Last update 20 Jul 3:52 pm EDT
Extended Forecast for

Potomac MD

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

    NOW until
    7:00pm Thu

    Heat Advisory

  • This
    Afternoon

    This Afternoon: Mostly sunny and hot, with a high near 99. Heat index values as high as 104. Southwest wind around 7 mph.

    Hot

    High: 99 °F

  • Tonight

    Tonight: Partly cloudy, with a low around 74. Southwest wind 3 to 6 mph.

    Partly Cloudy

    Low: 74 °F

  • Friday

    Friday: A slight chance of showers and thunderstorms.  Mostly sunny, with a high near 95. Heat index values as high as 102. Northwest wind 6 to 8 mph.  Chance of precipitation is 20%.

    Slight Chance
    T-storms

    High: 95 °F

  • Friday
    Night

    Friday Night: A chance of showers and thunderstorms, mainly before 2am.  Partly cloudy, with a low around 76. Northwest wind around 6 mph becoming calm  after midnight.  Chance of precipitation is 30%.

    Chance
    T-storms

    Low: 76 °F

  • Saturday

    Saturday: A chance of showers and thunderstorms, mainly after 8am.  Partly sunny, with a high near 94. Calm wind becoming southwest around 6 mph in the afternoon.  Chance of precipitation is 50%.

    Chance
    T-storms

    High: 94 °F

  • Saturday
    Night

    Saturday Night: A chance of showers and thunderstorms.  Mostly cloudy, with a low around 75. Chance of precipitation is 50%.

    Chance
    T-storms

    Low: 75 °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 75. Chance of precipitation is 30%.

    Chance
    T-storms

    Low: 75 °F

Detailed Forecast

This Afternoon
Mostly sunny and hot, with a high near 99. Heat index values as high as 104. Southwest wind around 7 mph.
Tonight
Partly cloudy, with a low around 74. Southwest wind 3 to 6 mph.
Friday
A slight chance of showers and thunderstorms. Mostly sunny, with a high near 95. Heat index values as high as 102. Northwest wind 6 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 76. 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 94. Calm wind becoming southwest around 6 mph in the afternoon. Chance of precipitation is 50%.
Saturday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 75. 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 75. 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
A chance of showers. Mostly cloudy, with a low around 71. Chance of precipitation is 30%.
Tuesday
Partly sunny, with a high near 85.
Tuesday Night
Partly cloudy, with a low around 68.
Wednesday
Mostly sunny, with a high near 85.
Wednesday Night
Partly cloudy, with a low around 68.
Thursday
Mostly sunny, with a high near 86.
Click Map For Forecast
Point Forecast:
Potomac MD
 39.02°N 77.2°W (Elev. 381 ft)
1:28 pm EDT Jul 20, 2017
4pm EDT Jul 20, 2017-6pm EDT Jul 27, 2017
 
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