Template:Dulles Airport weatherbox
| Climate data for Dulles International Airport in Sterling, Virginia (1991−2020 normals,[a] extremes 1960−present) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °F (°C) | 79 (26) |
80 (27) |
89 (32) |
93 (34) |
97 (36) |
102 (39) |
105 (41) |
104 (40) |
99 (37) |
96 (36) |
84 (29) |
79 (26) |
105 (41) |
| Mean maximum °F (°C) | 65.6 (18.7) |
67.1 (19.5) |
76.5 (24.7) |
85.8 (29.9) |
89.9 (32.2) |
94.1 (34.5) |
96.7 (35.9) |
95.4 (35.2) |
91.3 (32.9) |
84.4 (29.1) |
74.4 (23.6) |
66.1 (18.9) |
97.7 (36.5) |
| Mean daily maximum °F (°C) | 42.6 (5.9) |
46.1 (7.8) |
54.8 (12.7) |
66.8 (19.3) |
75.0 (23.9) |
83.1 (28.4) |
87.6 (30.9) |
86.3 (30.2) |
79.3 (26.3) |
67.8 (19.9) |
56.5 (13.6) |
46.5 (8.1) |
66.0 (18.9) |
| Daily mean °F (°C) | 33.9 (1.1) |
36.4 (2.4) |
44.2 (6.8) |
55.0 (12.8) |
64.0 (17.8) |
72.5 (22.5) |
77.2 (25.1) |
75.7 (24.3) |
68.6 (20.3) |
56.6 (13.7) |
46.0 (7.8) |
37.7 (3.2) |
55.7 (13.2) |
| Mean daily minimum °F (°C) | 25.2 (−3.8) |
26.7 (−2.9) |
33.6 (0.9) |
43.2 (6.2) |
53.0 (11.7) |
61.9 (16.6) |
66.8 (19.3) |
65.2 (18.4) |
57.9 (14.4) |
45.3 (7.4) |
35.6 (2.0) |
29.0 (−1.7) |
45.3 (7.4) |
| Mean minimum °F (°C) | 6.6 (−14.1) |
9.6 (−12.4) |
16.8 (−8.4) |
27.8 (−2.3) |
37.0 (2.8) |
48.3 (9.1) |
55.4 (13.0) |
54.4 (12.4) |
43.0 (6.1) |
29.9 (−1.2) |
20.6 (−6.3) |
13.4 (−10.3) |
3.8 (−15.7) |
| Record low °F (°C) | −18 (−28) |
−14 (−26) |
−1 (−18) |
17 (−8) |
28 (−2) |
36 (2) |
41 (5) |
38 (3) |
30 (−1) |
15 (−9) |
9 (−13) |
−4 (−20) |
−18 (−28) |
| Average precipitation inches (mm) | 2.94 (75) |
2.61 (66) |
3.50 (89) |
3.47 (88) |
4.72 (120) |
4.30 (109) |
4.15 (105) |
3.53 (90) |
3.94 (100) |
3.65 (93) |
3.13 (80) |
3.30 (84) |
43.24 (1,098) |
| Average snowfall inches (cm) | 6.9 (18) |
7.0 (18) |
3.9 (9.9) |
0.1 (0.25) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.3 (0.76) |
2.8 (7.1) |
21.0 (53) |
| Average extreme snow depth inches (cm) | 4.3 (11) |
4.3 (11) |
2.5 (6.4) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.1 (0.25) |
1.9 (4.8) |
7.5 (19) |
| Average precipitation days (≥ 0.01 in) | 10.3 | 9.1 | 11.0 | 11.0 | 12.7 | 10.8 | 11.0 | 9.3 | 9.0 | 8.1 | 8.6 | 10.2 | 121.1 |
| Average snowy days (≥ 0.1 in) | 3.1 | 2.9 | 1.8 | 0.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.2 | 1.6 | 9.7 |
| Average relative humidity (%) | 68.1 | 66.0 | 63.9 | 62.6 | 70.4 | 72.3 | 73.0 | 74.8 | 75.4 | 73.0 | 70.0 | 69.6 | 69.9 |
| Average dew point °F (°C) | 20.7 (−6.3) |
22.3 (−5.4) |
30.2 (−1.0) |
38.7 (3.7) |
51.4 (10.8) |
60.6 (15.9) |
64.9 (18.3) |
64.0 (17.8) |
57.6 (14.2) |
45.0 (7.2) |
35.1 (1.7) |
25.7 (−3.5) |
43.0 (6.1) |
| Source: National Weather Service (relative humidity and dew point 1962–1990)[1][2][3] | |||||||||||||
Notes[edit]
- ^ Mean monthly maxima and minima (i.e. the expected highest and lowest temperature readings at any point during the year or given month) calculated based on data at said location from 1991 to 2020.
References[edit]
- ^ "NowData – NOAA Online Weather Data". National Oceanic and Atmospheric Administration. Retrieved July 5, 2021.
- ^ "Station: Washington DC DULLES AP, VA". U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991–2020). National Oceanic and Atmospheric Administration. Retrieved July 5, 2021.
- ^ "WMO Climate Normals for WASHINGTON DC/DULLES INT'L AR, VA 1961–1990". National Oceanic and Atmospheric Administration. Retrieved May 4, 2015.