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
2025
2024
2023
2022
2021
January
84.6
88
84
81
82
81
February
86.4
77
83
88
87
86
March
84.3
78
87
78
84
84
April
86.9
92
91
76
76
May
89.2
92
81
86
96
89
June
89.8
96
84
95
93
July
92.8
93
96
85
99
August
93.6
99
96
91
94
September
93.7
95
82
89
95
October
92.2
93
87
100
94
November
83.2
87
91
93
75
December
82.9
85
90
79
85
Average
88.6
84.2
90.0
87.7
88.4
88.5
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
2025
2024
2023
2022
2021
January
-10.3
-6.4
-8.5
-11.3
-14.5
-6.5
February
-10.4
-9.5
-6.7
-13.6
-13.0
-6.0
March
-3.6
-4.7
-1.7
-2.9
-4.0
-2.8
April
4.1
7.5
5.2
3.2
5.0
May
10.3
11.5
11.0
11.4
11.3
9.9
June
17.1
21.8
18.0
18.5
18.1
July
22.6
24.6
25.1
19.6
23.5
August
21.3
23.5
19.6
22.3
22.3
September
15.9
17.8
17.1
17.1
15.1
October
8.9
9.0
10.5
11.0
9.8
November
-1.8
2.3
-1.4
-2.6
1.8
December
-5.3
-5.5
-3.7
-2.9
-6.2
Average
5.4
-2.7
8.3
6.7
6.2
7.3
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2025
2024
2023
2022
2021
January
-19.6
-12.5
-18.1
-20.6
-24.1
-13.5
February
-20.1
-18.8
-15.3
-25.1
-25.8
-16.6
March
-12.0
-15.4
-9.9
-9.6
-15.9
-13.4
April
-5.9
-2.1
-5.7
-3.9
-1.4
May
0.7
-1.9
2.2
0.5
0.8
1.9
June
7.2
9.9
7.2
7.4
8.5
July
12.5
12.4
16.6
11.6
11.3
August
12.0
11.8
11.9
12.5
12.9
September
7.2
7.7
7.9
8.5
8.0
October
2.0
0.7
4.0
3.5
2.2
November
-6.2
-3.3
-7.0
-8.9
-4.9
December
-13.9
-12.6
-10.3
-9.5
-13.5
Average
-4.6
-11.3
-1.0
-2.0
-3.4
-1.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
49.1
58
48
51
43
53
February
45.0
48
50
37
47
32
March
39.0
38
36
40
40
37
April
30.1
29
18
49
31
May
27.2
19
43
32
22
34
June
24.2
15
22
28
23
July
18.7
17
13
32
14
August
20.2
13
28
20
17
September
18.6
12
29
31
28
October
19.5
21
17
14
18
November
39.5
36
35
38
42
December
44.4
44
43
30
42
Average
30.0
37.2
28.1
28.6
32.2
28.9
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
2025
2024
2023
2022
2021
January
9.5
11
11
8
8
8
February
10.0
11
8
10
10
10
March
9.8
8
9
9
12
10
April
9.3
10
9
9
6
May
9.4
10
9
10
9
10
June
8.6
9
9
9
8
July
8.1
9
7
9
7
August
7.6
7
7
7
9
September
9.7
8
9
9
10
October
9.8
8
10
10
8
November
9.5
9
11
8
8
December
9.9
10
11
9
10
Average
9.2
9.7
8.8
8.8
9.0
8.5
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2025
2024
2023
2022
2021
January
285°
287°
265°
271°
275°
February
274°
241°
258°
272°
254°
March
265°
004°
017°
328°
280°
April
262°
352°
024°
021°
May
347°
034°
346°
323°
321°
June
333°
046°
329°
255°
July
261°
190°
005°
246°
August
262°
339°
262°
276°
September
259°
352°
274°
323°
October
280°
328°
241°
354°
November
348°
282°
299°
280°
December
241°
296°
197°
276°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.