5-day weather forecast for Great Falls, Virginia

Weather changeability for Herndon, Virginia

Temperature Last Month Last Year
Average change in high temperature day-to-day 9.3° 6.2°
Average change in low temperature day-to-day 11.9° 8.0°
Precipitation Last Month Last Year
Chance of dry day after a precip day 41% 61%
Chance of precip day after a dry day 64% 28%

Weather forecast accuracy for Herndon, Virginia

Last Month
NWS Digital Forecast   75.30%
Foreca   74.70%
The Weather Channel   72.02%
Weather Underground   72.02%
AccuWeather   70.83%
MeteoGroup   68.45%
World Weather Online   63.69%
Dark Sky (forecast.io)   61.61%
Persistence   33.93%
Last Year
Weather Underground   77.10%
The Weather Channel   77.03%
MeteoGroup   76.58%
AccuWeather   76.09%
Foreca   75.14%
Dark Sky (forecast.io)   70.21%
NWS Digital Forecast   69.11%
World Weather Online   59.05%
Persistence   42.91%

ForecastAdvisor Fact

1.8% of Foreca's low temperature forecasts for Herndon were off by more than 10 degrees last year.