Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 5 mi 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
77.7
91
66
60
93
76
February
87.2
92
93
86
92
89
March
89.5
88
89
88
89
96
April
92.1
90
94
92
97
May
93.8
98
94
95
98
June
94.5
94
88
95
96
July
97.5
94
98
96
99
August
95.5
94
96
96
97
September
94.0
95
96
93
100
October
92.5
100
92
95
90
November
90.7
89
93
89
99
December
83.3
76
73
78
87
Average
91.1
90.3
90.4
88.9
92.4
94.2
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 3⅛ mi 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
-1.3
-1.1
-2.0
2.2
-3.0
0.4
February
2.5
0.7
10.0
4.4
1.7
-5.7
March
9.6
13.3
12.0
7.4
10.0
12.0
April
15.4
16.8
16.8
13.0
17.6
May
22.6
25.0
24.0
23.5
22.0
June
28.3
28.8
28.1
28.8
30.3
July
29.0
27.8
28.5
28.8
29.1
August
28.0
28.0
27.6
27.6
29.8
September
25.2
26.6
25.1
23.6
27.8
October
17.3
21.0
17.1
17.6
19.3
November
8.7
10.4
9.6
10.8
9.3
December
4.0
2.7
5.9
3.1
6.5
Average
14.6
4.4
17.2
16.4
15.9
16.7
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
-8.1
-11.8
-8.7
-4.0
-13.0
-6.5
February
-7.0
-9.3
-3.3
-6.5
-9.9
-13.8
March
-1.6
0.7
1.1
-2.8
-1.4
1.3
April
4.1
6.0
3.2
3.2
6.2
May
10.9
11.6
9.5
12.6
10.3
June
16.6
18.1
14.5
15.8
18.5
July
18.5
17.6
16.3
18.6
18.8
August
17.1
17.0
17.1
17.6
18.1
September
13.8
13.0
14.5
13.1
13.9
October
6.7
7.2
7.2
4.5
10.4
November
-1.8
3.1
-2.8
0.3
-1.1
December
-4.4
-5.5
-1.9
-4.2
-3.7
Average
4.5
-6.0
6.7
5.9
5.4
6.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
19.1
12
20
32
13
18
February
12.5
9
2
18
14
12
March
12.2
16
13
14
20
7
April
13.9
20
14
16
7
May
9.5
7
8
13
10
June
5.4
8
4
6
5
July
3.2
7
4
5
4
August
3.5
5
3
5
1
September
6.0
5
8
7
2
October
10.3
0
17
9
14
November
11.8
15
7
24
10
December
14.0
18
20
22
8
Average
10.0
12.4
9.6
11.7
11.9
7.6
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
8.8
11
8
7
10
8
February
9.3
9
9
9
11
9
March
10.0
11
10
9
9
11
April
10.2
10
10
11
10
May
8.1
8
6
9
9
June
7.7
9
6
8
7
July
6.4
5
5
7
7
August
6.6
6
6
6
6
September
7.1
6
6
7
8
October
8.7
9
9
8
7
November
9.3
9
9
10
10
December
8.4
9
8
8
9
Average
8.5
10.2
8.1
7.5
8.6
8.2
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
261°
260°
269°
280°
343°
February
287°
241°
259°
261°
297°
March
237°
268°
295°
296°
187°
April
264°
245°
238°
256°
May
241°
003°
180°
187°
June
237°
338°
250°
227°
July
210°
253°
261°
312°
August
257°
248°
239°
206°
September
357°
146°
298°
256°
October
233°
266°
257°
328°
November
258°
236°
233°
250°
December
263°
242°
210°
244°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.