Herndon Weather Forecast
- 67
- 92
Rain Showers
- 61
- 77
Chance Rain Showers
- 59
- 81
Partly Sunny
- 60
- 83
Partly Sunny
- 63
- 84
Partly Sunny
- 66
- 85
Slight Chance Rain Showers
Today 31 Jul Eastern Loudoun
Mostly sunny with a slight chance of Showers and Thunderstorms in the Morning, then mostly cloudy with Showers with Thunderstorms likely in the afternoon. Some Thunderstorms may produce heavy rainfall in the afternoon. Locally heavy rainfall possible in the afternoon. Highs in the lower 90s. South Winds around 5 Mph. Chance of rain 90 percent.
Tonight 31 Jul Eastern Loudoun
Mostly cloudy. Showers with Thunderstorms likely in the Evening, then a chance of Showers with a slight chance of Thunderstorms after midnight. Some Thunderstorms may produce heavy rainfall. Lows in the upper 60s. North Winds 5 to 10 Mph. Chance of rain 90 percent.
Herndon Temperature Statistics
July Temperature
Washington/Dulles International Airport, DC (4.3 miles)
Lowest 5 July, 2025
60.7 °FAverage July
79.9 °FHighest 25 July, 2025
97.6 °F
Climate (2020–Present)
Washington/Dulles International Airport, DC (4.3 miles)
Average Low 2020–2025
47.9 °FAverage 2020–2025
58.3 °FAverage High 2020–2025
68.5 °F