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

Watching Hurricane Erin; Heavy Rainfall Threat for Upper Midwest; Heatrisk for Mississippi Valley

Hurricane Erin continues to track westward with its outer bands bringing heavy rainfall and gusty winds for Puerto Rico and US Virgin Islands. Life-threatening surf and rip currents are occurring and will spread across the Atlantic coasts this week. Meanwhile, heavy rainfall and possible flooding are in the forecast for upper Midwest through Monday. Heatrisk continues for the Mississippi Valley. Read More >

Current conditions at

Washington/Dulles International Airport, DC (KIAD)

Lat: 38.93°NLon: 77.45°WElev: 312ft.

Mostly Cloudy

74°F

23°C

Humidity 88%
Wind Speed NW 7 mph
Barometer 29.94 in (1013.6 mb)
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Last update 18 Aug 2:52 am EDT
Extended Forecast for

2 Miles S Herndon VA

  • Overnight

    Overnight: Mostly cloudy, with a low around 69. Northwest wind around 6 mph.

    Low: 69 °F

    Mostly Cloudy

  • Monday

    Monday: A slight chance of showers before 3pm, then a slight chance of showers after 5pm. Mostly cloudy, with a high near 76. Northeast wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.

    High: 76 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

  • Monday Night

    Monday Night: Cloudy, with a low around 66. Northeast wind 6 to 8 mph.

    Low: 66 °F

    Cloudy

  • Tuesday

    Tuesday: A slight chance of showers after 8am. Patchy fog between 9am and 10am. Otherwise, mostly cloudy, with a high near 74. East wind around 6 mph. Chance of precipitation is 20%.

    High: 74 °F

    Slight Chance
    Showers and
    Patchy Fog

  • Tuesday Night

    Tuesday Night: A slight chance of showers before 2am. Mostly cloudy, with a low around 67. East wind 3 to 6 mph. Chance of precipitation is 20%.

    Low: 67 °F

    Slight Chance
    Showers

  • Wednesday

    Wednesday: A slight chance of showers after 2pm. Partly sunny, with a high near 82. Chance of precipitation is 20%.

    High: 82 °F

    Partly Sunny
    then Slight
    Chance
    Showers

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 68.

    Low: 68 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 83.

    High: 83 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 66.

    Low: 66 °F

    Partly Cloudy

Detailed Forecast

Overnight
Mostly cloudy, with a low around 69. Northwest wind around 6 mph.
Monday
A slight chance of showers before 3pm, then a slight chance of showers after 5pm. Mostly cloudy, with a high near 76. Northeast wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
Monday Night
Cloudy, with a low around 66. Northeast wind 6 to 8 mph.
Tuesday
A slight chance of showers after 8am. Patchy fog between 9am and 10am. Otherwise, mostly cloudy, with a high near 74. East wind around 6 mph. Chance of precipitation is 20%.
Tuesday Night
A slight chance of showers before 2am. Mostly cloudy, with a low around 67. East wind 3 to 6 mph. Chance of precipitation is 20%.
Wednesday
A slight chance of showers after 2pm. Partly sunny, with a high near 82. Chance of precipitation is 20%.
Wednesday Night
Partly cloudy, with a low around 68.
Thursday
Mostly sunny, with a high near 83.
Thursday Night
Partly cloudy, with a low around 66.
Friday
Mostly sunny, with a high near 85.
Friday Night
Partly cloudy, with a low around 67.
Saturday
Mostly sunny, with a high near 86.
Saturday Night
Partly cloudy, with a low around 69.
Sunday
A chance of showers. Partly sunny, with a high near 86. Chance of precipitation is 40%.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
2 Miles S Herndon VA
 38.95°N 77.39°W (Elev. 384 ft)
Last Update:
1:30 am EDT Aug 18, 2025
Forecast Valid:
3am EDT Aug 18, 2025-6pm EDT Aug 24, 2025
 
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