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
70.5
54
69
58
75
86
February
76.3
74
75
66
91
79
March
73.8
64
64
72
75
80
April
70.6
67
63
68
61
74
May
73.9
63
65
76
72
77
June
70.0
73
74
75
58
66
July
67.4
61
56
56
81
81
August
77.4
77
76
77
84
September
86.1
90
79
84
84
October
88.5
69
98
85
94
November
75.9
71
70
88
72
December
70.5
56
71
69
77
Average
75.1
64.4
68.1
71.8
75.4
79.0
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
-15.4
-11
-14
-19
-10
-13
February
-16.6
-12
-18
-18
-11
-14
March
-9.2
-7
-10
-10
-8
-7
April
-2.7
1
-1
-1
3
-3
May
6.6
9
8
9
8
4
June
12.8
15
17
18
10
12
July
17.3
17
19
15
17
21
August
16.6
18
17
18
19
September
12.9
16
15
14
12
October
7.1
8
9
11
4
November
-2.3
-1
-1
1
-2
December
-8.0
-4
-7
-8
-8
Average
1.8
0.6
3.3
2.6
3.9
2.0
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
-22.4
-19
-21
-26
-17
-20
February
-25.4
-20
-28
-28
-22
-24
March
-19.1
-16
-19
-18
-19
-19
April
-10.2
-7
-8
-10
-5
-10
May
-2.3
3
-1
-1
-2
-3
June
3.7
7
6
7
1
3
July
8.0
9
10
6
8
12
August
8.6
9
10
8
10
September
6.2
7
7
8
7
October
2.1
3
4
6
-1
November
-7.9
-6
-6
-2
-7
December
-14.1
-9
-13
-14
-16
Average
-6.0
-8.6
-5.4
-6.7
-5.9
-6.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
50.7
74
61
53
26
55
February
34.6
53
42
35
20
35
March
39.6
57
53
45
33
31
April
32.3
39
43
39
4
33
May
26.9
25
40
27
17
36
June
14.6
15
4
18
19
16
July
14.9
19
24
14
5
8
August
10.7
16
11
10
6
September
18.4
13
26
16
26
October
22.5
32
23
23
25
November
51.4
62
64
38
47
December
55.9
69
45
60
47
Average
27.9
40.9
37.1
31.5
19.8
27.1
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
8.8
10
9
10
6
8
February
9.0
8
10
10
8
8
March
8.6
9
7
9
11
9
April
8.6
10
7
9
6
9
May
9.2
10
9
10
10
9
June
8.1
8
5
10
8
7
July
8.1
8
6
8
8
9
August
8.4
7
9
10
7
September
10.0
8
10
10
12
October
9.6
8
10
8
10
November
10.7
12
11
10
11
December
11.0
12
12
11
10
Average
9.0
8.7
8.1
9.6
8.7
9.0
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
236°
204°
211°
161°
198°
February
291°
198°
220°
172°
234°
March
233°
293°
251°
309°
178°
April
313°
324°
003°
060°
292°
May
332°
298°
234°
303°
287°
June
258°
005°
196°
297°
340°
July
266°
250°
260°
283°
349°
August
315°
235°
229°
328°
September
266°
287°
180°
249°
October
264°
221°
134°
222°
November
217°
283°
033°
225°
December
241°
285°
188°
187°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.