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
74.4
63
87
75
67
73
February
75.9
71
62
69
86
82
March
81.7
72
82
68
87
87
April
82.4
73
78
92
89
May
89.9
94
87
95
88
June
89.5
79
88
90
89
July
93.0
89
90
94
90
August
91.3
90
91
96
93
September
86.5
80
78
86
94
October
76.9
61
87
75
83
November
66.7
67
61
69
70
December
69.6
72
61
70
66
Average
81.6
68.9
78.4
79.2
85.6
85.1
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
-9.7
-7
-6
-13
-7
-6
February
-7.9
-2
-6
-8
-6
-6
March
0.0
3
-1
-1
3
1
April
7.4
8
7
13
6
May
16.5
18
20
17
15
June
22.4
24
22
23
23
July
25.0
25
24
23
27
August
22.8
22
23
25
22
September
18.1
21
18
17
16
October
10.2
11
12
14
6
November
0.4
0
3
2
4
December
-6.8
-2
-4
-4
-5
Average
7.3
-3.9
9.7
9.0
10.1
8.6
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
-19.9
-14
-15
-27
-14
-16
February
-19.8
-13
-19
-23
-20
-16
March
-12.0
-8
-12
-13
-10
-11
April
-5.9
-3
-3
-2
-5
May
3.4
3
6
3
2
June
9.4
10
10
11
10
July
12.3
13
12
11
15
August
10.8
9
11
14
11
September
7.3
7
7
8
7
October
2.1
4
3
4
-2
November
-7.4
-7
-4
-5
-3
December
-14.0
-9
-12
-14
-13
Average
-4.5
-12.1
-2.5
-3.6
-2.8
-2.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
54.9
66
43
57
47
62
February
48.7
49
61
56
27
48
March
34.2
39
37
52
29
26
April
27.6
41
29
16
24
May
16.5
15
18
12
19
June
14.7
13
19
15
18
July
9.7
10
21
7
15
August
10.6
15
14
4
14
September
15.9
19
22
17
18
October
30.6
39
24
21
33
November
51.0
60
51
44
39
December
51.1
38
48
57
58
Average
30.2
50.2
30.6
31.5
22.1
28.3
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
7.1
7
7
7
6
7
February
8.1
8
8
8
7
9
March
8.5
8
8
8
10
8
April
8.5
9
8
8
8
May
7.8
8
7
8
8
June
7.4
7
8
8
7
July
7.0
6
8
7
6
August
6.8
7
6
8
7
September
7.2
6
7
8
8
October
7.6
7
9
6
7
November
8.2
8
9
8
8
December
7.2
7
7
7
8
Average
7.6
7.8
7.2
7.7
7.5
7.6
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
237°
302°
248°
292°
282°
February
266°
228°
267°
249°
253°
March
274°
323°
271°
259°
249°
April
214°
257°
340°
288°
May
330°
211°
276°
311°
June
018°
249°
267°
254°
July
263°
258°
305°
256°
August
298°
257°
236°
276°
September
268°
310°
244°
237°
October
282°
214°
173°
235°
November
232°
254°
246°
221°
December
267°
233°
227°
278°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.