Washington Dulles Airport
The tables below display average monthly climate and weather indicators in Washington Dulles Airport District of Columbia.
Temperature by: Fahrenheit / Centigrade
| Washington Dulles Airport Temperature |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Annual |
| Avg. Temperature | 30.6 | 33.6 | 43.2 | 52.7 | 62.2 | 71.0 | 75.6 | 74.2 | 67.1 | 55.1 | 45.4 | 35.4 | 53.8 |
| Avg. Max Temperature | 40.1 | 43.8 | 54.6 | 65.1 | 74.3 | 82.8 | 87.0 | 85.5 | 78.9 | 67.7 | 56.7 | 45.0 | 65.1 |
| Avg. Min Temperature | 21.0 | 23.3 | 31.8 | 40.3 | 50.0 | 59.2 | 64.1 | 62.8 | 55.4 | 42.4 | 34.2 | 25.8 | 42.5 |
| Days with Max Temp of 90 F or Higher | 0.0 | 0.0 | 0.0 | < 0.5 | 1.0 | 5.0 | 12.0 | 8.0 | 3.0 | < 0.5 | 0.0 | 0.0 | 29.0 |
| Days with Min Temp Below Freezing | 26.0 | 22.0 | 17.0 | 6.0 | < 0.5 | 0.0 | 0.0 | 0.0 | < 0.5 | 5.0 | 15.0 | 23.0 | 114 |
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| Washington Dulles Airport Heating and Cooling |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Annual |
| Heating Degree Days | 1066 | 879 | 676 | 369 | 140 | 7.0 | 0.0 | 0.0 | 44.0 | 319 | 588 | 918 | 5006 |
| Cooling Degree Days | 0.0 | 0.0 | 0.0 | 0.0 | 53.0 | 187 | 329 | 285 | 107 | 12.0 | 0.0 | 0.0 | 973 |
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| Washington Dulles Airport Precipitation |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Annual |
| Precipitation (inches) | 2.7 | 2.8 | 3.2 | 3.1 | 4.0 | 3.9 | 3.5 | 3.9 | 3.4 | 3.2 | 3.3 | 3.2 | 40.2 |
| Days with Precipitation 0.01 inch or More | 10.0 | 9.0 | 10.0 | 10.0 | 12.0 | 10.0 | 10.0 | 9.0 | 9.0 | 8.0 | 9.0 | 10.0 | 118 |
| Monthly Snowfall (inches) | 7.4 | 6.8 | 3.4 | 0.4 | < 0.05 | < 0.05 | 0.0 | < 0.05 | 0.0 | 0.0 | 1.2 | 3.5 | 22.7 |
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| Other Washington Dulles Airport Weather Indicators |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Annual |
| Average Wind Speed | 8.2 | 8.6 | 9.0 | 8.8 | 7.4 | 6.8 | 6.2 | 5.8 | 6.2 | 6.6 | 7.6 | 7.7 | 7.4 |
| Clear Days | 7.0 | 7.0 | 7.0 | 7.0 | 7.0 | 6.0 | 8.0 | 8.0 | 9.0 | 11.0 | 7.0 | 7.0 | 92.0 |
| Partly Cloudy Days | 7.0 | 6.0 | 8.0 | 9.0 | 10.0 | 12.0 | 11.0 | 11.0 | 9.0 | 8.0 | 8.0 | 7.0 | 105 |
| Cloudy Days | 17.0 | 15.0 | 16.0 | 14.0 | 14.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 15.0 | 17.0 | 168 |
| Percent of Possible Sunshine | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Avg. Relative Humidity | 53.5 | 68.5 | 66.5 | 64.0 | 65.5 | 69.5 | 71.0 | 72.0 | 72.5 | 72.5 | 68.5 | 67.0 | 70.5 |
Weather information for other cities in District of Columbia