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
88.8
93
89
91
93
85
February
95.3
88
98
97
100
90
March
96.8
96
92
99
98
97
April
96.3
100
95
90
97
May
96.8
97
98
100
99
June
97.2
97
100
99
92
July
98.9
100
100
100
97
August
98.3
99
97
99
97
September
97.7
98
99
99
97
October
93.6
88
99
94
95
November
88.3
84
99
92
82
December
89.0
89
93
74
86
Average
95.2
92.6
95.0
97.5
96.2
93.8
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
5.1
6.5
5.7
6.0
5.5
3.3
February
8.4
6.7
11.0
8.0
9.0
9.5
March
11.7
12.5
13.3
11.5
12.5
11.0
April
15.3
15.6
12.5
13.3
12.8
May
19.0
19.3
18.6
21.3
16.0
June
24.7
22.8
26.5
25.5
25.6
July
25.8
25.3
26.3
27.1
23.8
August
25.7
27.3
25.1
27.1
21.8
September
21.2
20.1
25.1
19.0
22.1
October
16.6
16.1
18.6
18.6
15.4
November
9.1
9.1
8.9
10.8
6.5
December
5.8
5.4
7.5
1.0
6.5
Average
15.0
8.6
15.9
16.3
16.4
14.5
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
-2.7
-2.3
-2.5
0.8
-1.0
-2.7
February
-1.9
-2.7
3.6
-1.7
1.0
-2.8
March
1.6
1.3
3.7
2.7
-1.8
0.3
April
4.2
5.2
4.2
3.5
1.6
May
8.5
9.6
9.3
9.0
6.7
June
13.2
13.1
13.1
13.4
13.9
July
14.3
14.5
14.4
14.4
13.8
August
14.5
15.3
15.0
14.5
12.9
September
10.2
11.5
11.9
9.4
10.0
October
6.8
7.5
7.0
8.8
4.5
November
1.9
2.2
3.2
2.5
0.7
December
0.3
-1.4
1.9
-4.7
1.1
Average
5.5
-1.4
7.0
7.0
6.3
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
20.7
12
18
15
14
32
February
13.5
15
12
10
11
19
March
14.9
12
19
19
6
16
April
14.2
17
20
22
15
May
13.7
23
13
7
18
June
10.1
17
3
9
11
July
8.7
12
10
4
10
August
9.9
6
16
8
17
September
10.0
17
4
18
6
October
12.6
11
16
10
8
November
16.0
4
29
15
17
December
19.9
9
23
20
18
Average
13.0
12.7
14.1
14.0
10.9
14.7
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
6.0
5
6
7
7
6
February
6.6
5
7
7
10
5
March
6.9
6
6
8
6
6
April
6.5
7
7
7
6
May
5.8
5
6
5
7
June
5.1
5
6
5
5
July
5.2
4
7
5
5
August
4.8
4
6
5
5
September
4.9
6
4
6
4
October
4.7
4
5
4
4
November
4.7
5
7
4
5
December
5.3
6
6
4
5
Average
5.5
5.3
5.4
6.1
5.6
5.3
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
215°
233°
236°
259°
234°
February
071°
231°
311°
240°
078°
March
019°
276°
245°
050°
274°
April
260°
332°
353°
321°
May
281°
020°
315°
255°
June
292°
020°
325°
343°
July
284°
262°
339°
292°
August
319°
271°
050°
293°
September
326°
063°
259°
019°
October
346°
233°
206°
276°
November
202°
234°
224°
242°
December
244°
238°
358°
220°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.