Currently: 55 °F. Overcast. (Weather station: Washington-Dulles International Airport, USA). See more current weatherAnnual Weather Averages Near Fairfax
Averages are for Washington-Dulles International Airport, which is 11 miles from Fairfax.
Based on weather reports collected during 1992–2021.
All Year Climate & Weather Averages in Fairfax
High Temp: 88 °F
Low Temp: 25 °F
Mean Temp: 56 °F
Precipitation: 3.65"
Humidity: 66%
Dew Point: 44 °F
Wind: 10 mph
Pressure: 30.06 "Hg
Visibility: 9 mi
January Climate & Weather Averages in Fairfax
High Temp: 43 °F
Low Temp: 25 °F
Mean Temp: 34 °F
Precipitation: 2.91"
Humidity: 64%
Dew Point: 23 °F
Wind: 12 mph
Pressure: 30.12 "Hg
Visibility: 9 mi
February Climate & Weather Averages in Fairfax
High Temp: 46 °F
Low Temp: 27 °F
Mean Temp: 36 °F
Precipitation: 2.71"
Humidity: 62%
Dew Point: 24 °F
Wind: 12 mph
Pressure: 30.10 "Hg
Visibility: 9 mi
March Climate & Weather Averages in Fairfax
High Temp: 55 °F
Low Temp: 33 °F
Mean Temp: 44 °F
Precipitation: 3.43"
Humidity: 59%
Dew Point: 30 °F
Wind: 13 mph
Pressure: 30.08 "Hg
Visibility: 9 mi
April Climate & Weather Averages in Fairfax
High Temp: 67 °F
Low Temp: 43 °F
Mean Temp: 55 °F
Precipitation: 3.53"
Humidity: 59%
Dew Point: 40 °F
Wind: 13 mph
Pressure: 30.00 "Hg
Visibility: 10 mi
May Climate & Weather Averages in Fairfax
High Temp: 75 °F
Low Temp: 53 °F
Mean Temp: 64 °F
Precipitation: 4.86"
Humidity: 67%
Dew Point: 52 °F
Wind: 10 mph
Pressure: 30.01 "Hg
Visibility: 9 mi
June Climate & Weather Averages in Fairfax
High Temp: 84 °F
Low Temp: 62 °F
Mean Temp: 73 °F
Precipitation: 4.21"
Humidity: 69%
Dew Point: 62 °F
Wind: 9 mph
Pressure: 29.98 "Hg
Visibility: 9 mi
July Climate & Weather Averages in Fairfax
High Temp: 88 °F
Low Temp: 67 °F
Mean Temp: 77 °F
Precipitation: 4.17"
Humidity: 68%
Dew Point: 66 °F
Wind: 8 mph
Pressure: 29.98 "Hg
Visibility: 9 mi
August Climate & Weather Averages in Fairfax
High Temp: 87 °F
Low Temp: 65 °F
Mean Temp: 76 °F
Precipitation: 3.71"
Humidity: 70%
Dew Point: 65 °F
Wind: 8 mph
Pressure: 30.02 "Hg
Visibility: 9 mi
September Climate & Weather Averages in Fairfax
High Temp: 79 °F
Low Temp: 58 °F
Mean Temp: 69 °F
Precipitation: 4.03"
Humidity: 71%
Dew Point: 59 °F
Wind: 9 mph
Pressure: 30.07 "Hg
Visibility: 9 mi
October Climate & Weather Averages in Fairfax
High Temp: 68 °F
Low Temp: 45 °F
Mean Temp: 57 °F
Precipitation: 3.94"
Humidity: 71%
Dew Point: 47 °F
Wind: 9 mph
Pressure: 30.08 "Hg
Visibility: 9 mi
November Climate & Weather Averages in Fairfax
High Temp: 57 °F
Low Temp: 35 °F
Mean Temp: 46 °F
Precipitation: 3.13"
Humidity: 66%
Dew Point: 35 °F
Wind: 11 mph
Pressure: 30.14 "Hg
Visibility: 9 mi
December Climate & Weather Averages in Fairfax
High Temp: 47 °F
Low Temp: 29 °F
Mean Temp: 38 °F
Precipitation: 3.16"
Humidity: 68%
Dew Point: 28 °F
Wind: 11 mph
Pressure: 30.13 "Hg
Visibility: 9 mi