Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 5 mi or more and a ceiling of 3,000 ft or more. Only observations between sunrise and sunset are taken into account.
Marginal VFR conditions (%)
Month
Average
2024
2023
2022
2021
2020
January
69.2
56
73
70
65
77
February
74.4
72
70
67
83
82
March
79.0
79
75
69
78
79
April
84.7
81
74
97
88
May
91.7
98
88
95
88
June
88.8
70
86
94
97
July
91.7
86
91
92
91
August
89.0
84
85
92
91
September
86.2
76
86
83
89
October
80.3
72
78
82
77
November
66.9
67
58
78
64
December
67.6
72
56
72
62
Average
81.7
68.7
77.4
76.5
85.7
83.9
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 3⅛ mi or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.
Maximum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-12.8
-9
-9
-17
-9
-10
February
-10.8
-6
-10
-12
-9
-8
March
-3.3
0
-3
-4
0
-2
April
4.5
7
4
10
3
May
13.8
15
16
15
12
June
20.6
23
20
21
22
July
23.2
23
22
22
25
August
20.9
21
21
24
21
September
16.5
20
17
16
14
October
8.6
10
11
13
4
November
-2.3
-2
1
0
1
December
-8.1
-4
-5
-8
-7
Average
4.9
-5.0
7.6
6.7
8.0
6.3
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-21.0
-17
-20
-30
-15
-20
February
-22.6
-17
-24
-26
-21
-19
March
-15.8
-11
-14
-15
-13
-16
April
-6.1
-5
-5
-2
-8
May
1.6
2
3
3
0
June
9.3
12
10
11
10
July
12.1
13
11
10
15
August
11.1
11
10
14
11
September
6.9
8
6
8
6
October
1.7
5
3
4
-2
November
-8.2
-9
-6
-5
-6
December
-17.7
-13
-13
-19
-15
Average
-6.9
-15.1
-3.2
-4.1
-3.9
-4.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
47.3
66
48
34
46
43
February
43.0
51
48
47
34
44
March
35.3
31
47
56
27
30
April
27.9
42
38
11
30
May
16.4
20
22
12
20
June
12.1
10
27
10
7
July
11.0
16
21
10
9
August
14.9
26
17
7
13
September
15.1
11
19
25
23
October
29.4
45
33
15
35
November
57.2
60
71
51
50
December
52.5
45
63
54
61
Average
28.7
49.3
33.7
36.4
22.3
27.0
Precipitation during daylight period
Percentage of observations with observed rain, drizzle, snow or hail. Only observations between sunrise and sunset are taken into account.
Wind speed (knots)
Month
Average
2024
2023
2022
2021
2020
January
7.4
8
7
8
7
7
February
8.3
8
8
9
7
9
March
8.7
8
8
9
10
9
April
8.8
9
10
8
9
May
8.4
10
8
8
8
June
7.8
7
8
8
8
July
7.0
4
8
7
7
August
7.2
7
7
8
7
September
7.4
6
7
8
9
October
8.1
8
9
6
8
November
8.6
8
9
9
8
December
7.5
7
8
8
8
Average
8.0
8.1
7.3
8.4
7.8
7.9
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
2020
January
218°
259°
230°
272°
259°
February
229°
216°
230°
240°
242°
March
272°
286°
257°
261°
212°
April
196°
265°
016°
268°
May
307°
258°
284°
300°
June
021°
202°
265°
251°
July
209°
248°
270°
246°
August
293°
236°
234°
271°
September
268°
264°
220°
232°
October
195°
204°
164°
220°
November
226°
224°
221°
211°
December
234°
197°
202°
225°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.