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
79.0
84
81
61
65
79
February
89.8
91
90
96
93
90
March
94.8
97
91
94
99
97
April
96.7
93
97
95
99
May
96.8
99
98
94
97
97
June
98.2
100
98
98
100
99
July
97.8
97
96
99
99
August
98.3
98
98
98
99
September
93.9
96
93
97
99
October
84.6
79
85
82
81
November
70.8
61
78
76
62
December
62.3
76
48
79
40
Average
91.0
95.3
89.9
88.6
92.0
89.4
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
2.4
4.7
3.2
2.9
1.0
-1.8
February
6.7
5.9
10.3
4.5
7.5
7.2
March
12.0
12.6
13.0
12.5
11.6
11.5
April
16.3
17.8
13.8
14.9
13.5
May
19.7
20.1
20.3
18.8
22.1
17.3
June
26.5
29.6
24.8
25.3
27.3
27.6
July
27.4
28.5
26.3
29.1
27.5
August
26.8
29.3
26.0
26.8
24.5
September
21.1
20.8
23.8
19.6
23.0
October
16.2
15.5
17.8
17.6
13.3
November
7.4
5.7
8.0
8.8
6.5
December
2.0
3.1
2.6
1.5
-1.7
Average
15.3
14.6
16.0
15.2
16.1
14.3
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
-6.7
-4.0
-5.4
-3.7
-6.2
-7.5
February
-3.3
-2.5
-1.9
-5.2
-3.2
-3.0
March
0.4
1.8
3.2
1.3
-3.9
-2.5
April
4.1
4.7
3.2
3.1
1.7
May
9.2
8.9
10.1
10.4
10.5
6.4
June
13.9
15.4
14.1
13.1
13.3
14.0
July
15.0
16.8
14.0
14.5
15.4
August
15.0
17.5
14.1
14.0
13.8
September
10.6
10.9
12.4
9.5
10.3
October
6.3
8.5
8.3
7.5
4.0
November
1.7
0.4
0.6
2.9
1.0
December
-4.9
-4.2
-3.9
-2.1
-5.9
Average
5.3
4.1
6.5
5.8
5.5
4.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
7.9
6
8
18
2
13
February
7.8
9
10
2
5
7
March
9.3
18
16
8
4
6
April
9.9
12
14
12
7
May
14.8
11
19
23
9
20
June
7.0
2
12
9
5
4
July
5.4
5
9
5
5
August
7.5
4
17
7
7
September
10.4
16
5
17
3
October
9.1
15
12
3
6
November
12.1
5
8
13
11
December
13.3
5
10
31
10
Average
9.4
9.0
10.8
11.5
8.4
8.0
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
2025
2024
2023
2022
2021
January
2.6
3
3
2
3
3
February
3.1
3
3
3
4
3
March
3.8
4
4
4
3
4
April
4.2
5
4
4
5
May
3.9
5
5
4
4
4
June
4.0
5
4
4
4
4
July
3.7
4
4
4
4
August
3.4
4
3
3
3
September
3.1
4
3
3
3
October
2.8
3
3
3
3
November
2.5
3
3
2
2
December
2.4
3
3
2
2
Average
3.4
4.0
3.5
3.3
3.4
3.4
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
185°
016°
010°
348°
337°
February
095°
345°
076°
016°
061°
March
307°
317°
327°
099°
021°
April
306°
046°
075°
321°
May
073°
125°
080°
078°
228°
June
101°
180°
058°
081°
300°
July
085°
021°
051°
247°
August
064°
050°
021°
035°
September
323°
068°
353°
063°
October
014°
309°
071°
045°
November
003°
331°
001°
307°
December
301°
339°
307°
316°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.