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
94.2
91
97
90
99
99
February
97.8
99
100
100
96
94
March
98.8
99
100
100
99
97
April
99.5
100
99
100
100
May
99.6
100
100
100
100
June
99.7
100
100
99
100
July
99.7
100
100
100
100
August
99.8
100
100
100
100
September
99.8
100
100
100
100
October
99.8
99
100
100
100
November
98.9
99
99
100
97
December
96.4
97
99
98
98
Average
98.6
96.5
99.3
98.8
99.3
99.0
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
5.9
8.1
7.4
7.9
5.7
6.5
February
8.7
8.0
11.4
8.3
8.4
8.8
March
11.7
13.6
13.0
11.6
8.3
9.5
April
15.5
18.3
13.8
14.5
13.4
May
20.1
20.5
18.8
21.8
20.8
June
25.3
28.1
24.0
26.8
25.6
July
28.3
30.8
29.3
28.3
28.8
August
28.7
30.6
28.1
27.6
29.8
September
23.8
23.3
24.8
23.3
23.5
October
18.5
19.3
20.3
18.5
14.8
November
12.8
11.5
13.1
13.5
13.0
December
8.2
7.9
9.4
11.0
7.0
Average
16.5
10.0
18.5
17.5
17.5
16.8
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
-1.1
1.1
0.5
1.3
-3.7
1.5
February
1.1
1.0
1.6
-1.5
0.4
2.6
March
4.4
5.2
4.7
4.4
0.9
3.0
April
6.8
6.9
5.5
5.7
6.7
May
11.3
11.0
11.3
10.0
13.5
June
15.0
15.3
15.0
14.1
16.8
July
15.2
16.1
14.5
14.1
17.1
August
15.1
15.1
15.0
14.1
16.6
September
11.8
11.9
13.0
11.5
11.3
October
7.9
8.1
10.0
7.5
6.0
November
5.6
3.2
5.5
6.7
6.4
December
1.8
1.0
1.1
5.2
0.7
Average
7.3
2.5
7.9
8.1
7.4
8.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
10.0
11
12
8
4
20
February
8.3
3
3
1
10
12
March
10.2
15
6
9
10
10
April
6.8
8
8
10
8
May
4.8
3
9
4
2
June
2.0
1
2
2
2
July
1.3
1
0
0
1
August
0.6
1
2
1
0
September
2.1
4
0
4
2
October
3.8
2
3
2
12
November
9.3
9
17
8
11
December
9.9
9
8
17
14
Average
5.7
9.7
4.3
5.1
5.1
6.7
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
5.3
5
6
5
5
6
February
5.5
5
5
6
5
5
March
6.1
6
5
6
7
7
April
5.3
6
5
6
6
May
4.7
6
5
4
6
June
4.6
5
4
5
4
July
4.8
5
4
5
4
August
4.8
6
5
5
5
September
5.1
6
5
5
5
October
4.5
5
5
4
5
November
5.3
7
7
5
4
December
5.4
6
5
5
6
Average
5.1
5.2
5.5
5.0
5.0
5.0
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
307°
323°
137°
333°
175°
February
154°
127°
111°
348°
140°
March
158°
165°
155°
017°
306°
April
162°
210°
161°
158°
May
160°
085°
150°
171°
June
165°
175°
215°
165°
July
171°
180°
352°
177°
August
163°
156°
352°
185°
September
183°
071°
176°
188°
October
155°
167°
078°
346°
November
288°
173°
141°
159°
December
345°
193°
184°
324°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.