Herndon, VA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Herndon, a town in Fairfax County, Virginia.
This Afternoon
73°F
Sunny
Sunny. High near 73, with temperatures falling to around 66 in the afternoon. Southeast wind around 7 mph.
7-day forecast for Herndon
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 73°F | Sunny | 7 mph SE | 2% |
| Tonight | 52°F | Mostly Clear | 7 mph S | 2% |
| Wednesday | 74°F | Mostly Sunny | 5 to 10 mph S | 2% |
| Wednesday Night | 62°F | Mostly Cloudy then Chance Light Rain | 9 mph S | 50% |
| Thursday | 75°F | Chance Light Rain | 10 mph S | 43% |
| Thursday Night | 61°F | Chance Light Rain | 2 to 7 mph SW | 49% |
| Friday | 70°F | Rain Likely | 5 mph NW | 61% |
| Friday Night | 50°F | Light Rain Likely | 2 to 7 mph NW | 61% |
| Saturday | 64°F | Mostly Sunny | 8 to 12 mph NW | 10% |
| Saturday Night | 43°F | Partly Cloudy | 8 mph NW | 10% |
| Sunday | 61°F | Mostly Sunny | 5 to 8 mph NW | 7% |
| Sunday Night | 42°F | Partly Cloudy then Slight Chance Light Rain | 5 to 8 mph NW | 19% |
| Monday | 61°F | Slight Chance Light Rain | 8 to 15 mph NW | 20% |
| Monday Night | 39°F | Slight Chance Light Rain | 5 to 8 mph W | 20% |
Forecast source: National Weather Service (api.weather.gov) for Herndon (38.970, -77.387). Updated through the day.
Growing snapshot for Herndon
Last spring frost
Apr 15
First fall frost
Oct 24
Growing season
194 days
Hardiness zone
7b
More local growing data for Herndon: nearby ZIP 20170 weather · frost dates · planting calendar · Virginia frost dates
Nearby towns & communities
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Burke Centre
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Clifton
Crosspointe
Difficult Run
Dranesville
Dunn Loring
Fair Lakes
Fair Oaks
Fairfax
Fairfax Station
Floris
Fort Belvoir
Fort Hunt
Franconia
Franklin Farm
George Mason
Great Falls
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Greenbriar
Groveton
Hayfield
Huntington
Climate data from the nearest NOAA station, Washington Dc Dulles Ap, Va (5.3 mi from Herndon). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.