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
2024
2023
2022
2021
January
77.5
88
82
87
76
February
86.8
92
83
96
79
March
96.0
96
98
99
93
April
98.2
100
97
97
98
May
98.6
98
98
98
100
June
99.0
99
99
98
100
July
98.5
99
99
99
97
August
98.0
98
99
97
98
September
95.4
98
96
92
98
October
84.6
87
91
76
87
November
71.2
73
93
60
71
December
73.4
70
70
77
77
Average
91.9
93.1
93.7
91.6
91.5
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
2024
2023
2022
2021
January
2.8
3.1
4.7
4.0
1.5
February
6.8
10.3
6.0
8.0
6.5
March
11.1
13.9
11.1
12.0
9.4
April
15.5
17.0
12.0
13.0
12.5
May
19.6
20.8
19.3
21.6
16.8
June
25.4
24.1
25.1
25.8
26.6
July
26.2
27.3
27.0
26.3
25.0
August
26.0
29.0
25.0
25.5
22.3
September
20.6
20.6
24.1
18.3
21.5
October
15.4
15.3
17.8
16.3
13.6
November
7.5
6.0
8.5
8.5
6.2
December
3.9
3.5
4.7
1.0
4.0
Average
15.1
15.9
15.5
15.5
13.8
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
January
-3.6
-4.6
0.1
-2.9
-3.0
February
-1.4
3.2
-1.1
0.2
-2.1
March
1.2
4.0
1.7
-1.3
-1.8
April
4.7
5.9
4.0
3.7
2.2
May
9.3
11.1
9.9
9.5
6.7
June
14.0
13.8
13.6
12.6
14.4
July
14.5
16.1
15.0
12.1
14.5
August
15.1
16.6
15.4
15.0
13.1
September
10.6
11.3
11.9
9.8
10.6
October
6.6
7.9
6.5
8.0
3.7
November
1.9
1.3
2.0
2.6
1.1
December
-1.1
-1.5
-1.0
-4.6
-1.5
Average
6.2
7.3
6.6
6.0
5.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
January
21.3
18
24
23
25
February
13.4
16
12
14
8
March
12.6
10
13
3
16
April
14.5
17
30
22
15
May
12.9
13
15
10
17
June
7.6
12
5
9
3
July
6.9
6
7
5
7
August
9.7
5
19
13
13
September
11.9
22
2
18
5
October
11.3
11
7
12
12
November
14.6
8
22
19
15
December
20.8
19
30
27
26
Average
12.4
12.4
14.5
13.2
12.5
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
2024
2023
2022
2021
January
7.7
8
6
10
7
February
7.8
8
9
11
6
March
7.9
7
9
7
7
April
7.5
7
7
8
8
May
6.9
7
7
6
8
June
6.5
6
6
6
6
July
6.3
6
6
7
6
August
5.6
6
6
5
6
September
5.7
8
5
6
5
October
6.0
6
5
4
6
November
6.0
6
8
5
6
December
6.6
6
7
6
7
Average
6.7
6.7
6.7
6.5
6.3
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
January
270°
266°
274°
269°
February
271°
281°
272°
078°
March
306°
275°
091°
285°
April
272°
280°
297°
279°
May
100°
092°
272°
266°
June
266°
328°
274°
285°
July
276°
266°
279°
273°
August
281°
261°
271°
273°
September
182°
042°
267°
283°
October
095°
276°
303°
251°
November
273°
273°
059°
267°
December
279°
273°
144°
267°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.