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
76.7
74
73
63
73
89
February
77.6
74
85
78
79
84
March
87.4
89
87
79
82
95
April
91.4
91
85
91
95
May
96.0
92
94
98
96
98
June
95.1
95
93
82
98
100
July
95.9
94
86
98
99
August
94.3
87
92
92
97
September
93.4
92
91
82
100
October
93.0
97
90
97
88
November
90.8
92
91
87
95
December
82.6
80
66
75
93
Average
90.3
85.5
89.0
83.7
88.3
94.8
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
-4.3
-5.5
-3.9
-1.0
-8.2
-4.7
February
-2.4
-5.9
2.2
-2.5
-3.6
-4.5
March
3.6
6.2
6.2
3.3
3.2
5.7
April
11.6
12.5
14.0
11.4
14.4
May
20.1
19.6
21.6
20.6
22.6
20.1
June
24.8
25.8
25.6
24.1
23.8
27.3
July
27.3
27.3
26.8
26.6
25.5
August
25.5
24.6
23.6
25.6
28.1
September
21.8
23.6
23.0
20.5
21.8
October
15.2
16.3
16.6
16.1
16.1
November
6.0
9.0
5.5
8.3
6.2
December
-1.6
-2.7
2.0
2.2
1.1
Average
12.2
8.8
13.8
13.1
13.0
13.4
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
-11.2
-11.0
-8.0
-7.4
-19.6
-9.1
February
-11.9
-12.1
-7.9
-11.0
-12.4
-12.5
March
-5.5
-4.3
-2.3
-4.2
-5.2
-5.7
April
2.0
2.9
2.7
1.9
3.2
May
8.9
9.8
11.5
7.5
9.8
8.6
June
14.5
15.0
16.1
14.3
14.4
16.3
July
17.4
17.6
18.3
17.3
16.0
August
16.1
16.0
15.0
16.6
18.5
September
11.8
12.6
13.0
11.5
12.5
October
6.3
6.9
9.4
4.9
7.5
November
-2.9
1.6
-2.8
1.0
-2.3
December
-7.1
-8.2
-4.6
-4.7
-8.7
Average
3.3
-1.8
5.1
4.6
3.6
4.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
38.4
56
43
56
39
24
February
30.2
42
26
41
39
26
March
23.7
32
29
37
32
9
April
22.0
32
26
25
18
May
12.0
23
13
15
14
4
June
10.8
10
19
18
17
8
July
8.2
11
17
9
6
August
9.9
22
14
11
5
September
8.6
12
12
14
5
October
14.1
10
28
7
16
November
19.8
21
17
29
17
December
30.5
36
40
39
22
Average
18.2
31.4
22.3
26.1
21.7
12.1
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
9.6
11
10
9
9
8
February
10.6
11
10
11
13
9
March
10.8
12
11
11
11
12
April
10.7
12
10
11
10
May
9.2
9
9
10
9
9
June
9.4
10
9
8
10
11
July
8.3
8
7
10
8
August
7.9
8
7
8
8
September
7.6
8
7
7
8
October
8.7
9
8
8
7
November
9.6
10
9
9
9
December
9.1
9
8
11
10
Average
9.4
10.4
9.2
8.7
9.5
9.0
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
259°
277°
306°
312°
276°
February
266°
228°
274°
256°
247°
March
239°
272°
291°
262°
242°
April
144°
250°
293°
330°
May
338°
203°
280°
222°
269°
June
231°
234°
022°
224°
231°
July
235°
221°
239°
242°
August
220°
236°
298°
226°
September
215°
263°
294°
233°
October
246°
231°
205°
346°
November
269°
239°
229°
248°
December
255°
343°
250°
261°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.