Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 8 km 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
67.6
51
70
68
72
70
February
76.3
75
80
74
84
77
March
91.4
84
96
89
90
89
April
97.5
100
97
97
95
May
98.3
98
99
97
99
98
June
99.6
100
100
100
100
98
July
99.5
100
99
100
100
August
99.3
99
99
100
99
September
98.5
97
100
98
100
October
94.9
92
98
97
97
November
81.4
88
94
80
79
December
54.8
40
58
81
54
Average
90.8
84.5
90.5
91.7
93.5
90.3
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 5 km 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
2.0
4.4
1.0
1.3
1.6
1.5
February
2.2
-3.1
4.0
1.8
6.2
1.3
March
9.4
11.4
9.5
11.8
5.7
5.4
April
17.3
22.8
15.8
17.8
14.4
May
22.4
23.1
22.1
20.8
20.1
23.1
June
28.6
27.3
30.8
25.3
29.3
26.6
July
31.1
34.1
29.3
30.5
33.1
August
31.0
31.5
31.3
33.6
31.0
September
24.5
27.3
24.8
22.5
21.3
October
17.3
16.6
17.6
15.3
14.3
November
7.5
6.7
10.5
7.9
8.9
December
2.3
2.5
3.9
2.1
3.2
Average
16.5
12.9
17.4
16.3
16.5
15.4
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
-4.2
-1.4
-7.7
-5.2
-5.9
-4.0
February
-5.7
-11.0
-2.3
-6.9
0.1
-6.2
March
-1.8
1.3
-1.0
2.7
-5.7
-2.1
April
5.9
8.9
7.7
6.7
5.4
May
10.3
10.0
7.7
9.5
8.3
12.0
June
15.6
13.9
16.3
14.0
14.9
16.6
July
17.7
19.3
16.6
16.1
18.1
August
17.3
17.3
17.3
20.3
18.8
September
11.9
15.0
11.5
11.0
9.9
October
6.5
6.4
5.7
6.5
3.7
November
1.0
1.3
3.6
1.9
1.1
December
-3.8
-1.0
-1.1
-4.3
-3.9
Average
6.4
2.9
6.9
6.5
6.5
6.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
30.1
21
26
15
50
22
February
22.7
18
15
25
25
21
March
15.1
11
4
12
24
32
April
12.3
3
18
12
23
May
7.8
4
3
14
9
7
June
4.7
8
2
7
2
7
July
2.8
1
2
2
3
August
2.0
1
1
4
3
September
4.5
0
6
8
7
October
8.4
10
8
14
3
November
19.5
17
25
15
20
December
33.9
42
39
14
33
Average
11.5
11.2
8.5
12.5
13.0
13.4
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
10.9
10
9
15
11
10
February
10.2
8
13
10
9
10
March
11.1
10
11
11
12
11
April
10.6
11
12
11
9
May
9.9
12
10
8
11
9
June
9.0
11
9
8
8
9
July
8.3
9
8
8
7
August
9.3
10
7
13
8
September
11.5
18
9
10
8
October
10.4
10
9
10
13
November
11.1
11
11
11
10
December
12.3
13
12
17
10
Average
10.2
10.4
11.1
9.6
10.5
9.4
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
181°
164°
113°
257°
127°
February
030°
121°
288°
251°
259°
March
183°
106°
239°
355°
028°
April
176°
117°
201°
309°
May
165°
086°
052°
282°
258°
June
278°
292°
041°
063°
274°
July
075°
277°
331°
051°
August
095°
055°
095°
100°
September
103°
075°
265°
352°
October
109°
249°
278°
088°
November
285°
187°
106°
133°
December
114°
156°
108°
112°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.