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
64.3
58
70
59
68
57
February
76.1
68
70
76
83
81
March
79.2
90
70
72
81
81
April
92.4
82
95
91
95
May
93.4
94
92
98
98
86
June
96.2
96
92
98
96
99
July
94.2
94
95
93
92
August
95.9
98
95
94
97
September
90.9
89
87
96
93
October
82.2
83
81
82
81
November
73.6
79
83
73
74
December
62.9
55
62
70
52
Average
86.5
85.5
84.1
86.6
88.5
85.8
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
4.1
4.2
2.5
5.5
5.5
2.1
February
4.7
3.2
6.4
5.2
6.2
2.7
March
7.2
9.5
7.2
6.7
7.4
7.5
April
11.1
10.9
10.5
10.5
9.6
May
16.0
15.5
18.3
15.5
15.5
13.9
June
20.4
19.5
18.3
21.8
19.6
21.1
July
21.3
20.5
20.3
21.3
23.1
August
21.5
21.3
20.0
23.3
20.0
September
17.8
18.6
20.1
16.6
18.1
October
13.1
13.3
12.6
14.4
13.0
November
7.9
7.7
6.0
8.9
8.5
December
4.9
6.4
4.5
1.1
3.7
Average
12.3
10.5
12.6
12.4
12.9
12.0
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
-1.9
0.0
-3.6
1.5
1.1
-2.3
February
-1.9
-2.3
2.0
0.2
1.1
-3.1
March
0.5
1.1
2.0
0.2
-1.3
-1.9
April
2.5
3.5
2.2
1.3
0.7
May
6.8
6.0
9.3
5.7
7.2
6.7
June
11.0
10.3
9.9
10.5
10.6
12.0
July
11.9
11.9
11.5
12.0
14.5
August
12.3
12.1
12.8
13.1
11.5
September
10.1
11.0
12.5
10.0
10.5
October
7.3
7.2
7.0
8.6
7.0
November
3.6
3.2
1.3
5.5
4.0
December
1.1
2.9
0.9
-4.6
-1.5
Average
5.4
3.2
6.0
5.5
5.8
5.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
20.9
17
25
26
18
24
February
17.0
9
23
12
18
14
March
12.9
4
8
24
4
10
April
8.2
16
6
8
8
May
8.2
11
7
2
10
17
June
5.9
11
8
3
5
3
July
8.2
10
12
4
8
August
8.6
7
13
7
10
September
8.9
12
3
8
7
October
12.4
9
16
5
17
November
13.2
11
22
7
14
December
18.8
14
24
16
23
Average
10.7
10.3
11.4
11.6
8.1
11.5
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
9.9
10
11
10
11
8
February
10.3
8
11
11
13
8
March
10.0
9
10
10
9
10
April
9.8
9
9
9
10
May
8.9
9
9
9
9
9
June
8.3
10
9
7
7
7
July
8.7
8
9
10
8
August
8.2
9
8
7
9
September
8.9
9
8
9
8
October
9.8
9
11
9
9
November
9.0
8
8
11
8
December
9.6
9
11
6
9
Average
9.2
9.3
9.0
9.1
9.1
8.6
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
232°
262°
222°
272°
261°
February
115°
233°
276°
249°
041°
March
258°
126°
243°
129°
269°
April
186°
086°
279°
311°
May
288°
106°
122°
263°
242°
June
254°
241°
301°
253°
290°
July
237°
236°
269°
234°
August
221°
247°
162°
271°
September
136°
197°
158°
225°
October
180°
239°
221°
222°
November
242°
163°
151°
250°
December
232°
236°
223°
201°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.