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
2024
2023
2022
2021
2020
January
76.7
75
69
90
66
73
February
85.4
75
89
84
86
95
March
87.8
82
86
82
91
91
April
83.1
73
75
78
89
May
89.7
95
86
88
88
June
93.4
91
94
94
89
July
93.7
96
96
84
98
August
90.5
84
87
90
88
September
86.0
85
82
98
91
October
85.5
81
91
83
91
November
81.3
78
84
90
78
December
77.4
70
72
74
82
Average
85.9
77.3
83.5
85.6
85.9
88.1
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
2024
2023
2022
2021
2020
January
-10.6
-9
-8
-15
-7
-2
February
-9.4
-3
-8
-12
-10
-7
March
-1.3
-1
-2
-2
3
1
April
5.6
4
4
9
6
May
16.0
19
15
16
16
June
22.6
25
21
24
22
July
25.2
23
24
26
27
August
22.8
23
23
24
23
September
17.2
20
18
18
15
October
8.5
9
11
13
4
November
-2.5
0
0
0
1
December
-7.4
-1
-8
-8
-7
Average
6.0
-5.4
8.6
7.3
9.0
7.3
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-21.8
-18
-18
-28
-16
-18
February
-22.6
-15
-21
-28
-24
-19
March
-16.6
-14
-18
-16
-13
-15
April
-7.2
-7
-6
-4
-7
May
1.7
2
3
2
1
June
8.1
9
8
9
8
July
11.6
10
12
10
15
August
10.3
9
11
13
13
September
6.1
7
5
7
6
October
0.3
1
1
4
-4
November
-9.3
-8
-7
-7
-7
December
-18.7
-9
-18
-20
-17
Average
-6.1
-16.1
-4.4
-5.3
-4.8
-5.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
33.2
44
38
31
25
36
February
33.6
45
43
39
30
26
March
24.1
48
26
37
16
20
April
23.2
45
42
16
17
May
13.1
15
21
15
16
June
8.8
11
14
6
12
July
5.1
8
10
3
2
August
8.0
13
10
7
11
September
13.8
10
22
10
18
October
20.4
35
17
10
16
November
40.6
42
42
31
35
December
34.4
35
43
43
38
Average
21.9
45.7
25.7
26.4
15.9
19.9
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
2020
January
5.6
6
5
7
5
5
February
6.6
6
8
7
6
7
March
7.2
8
6
7
8
7
April
6.9
7
8
7
8
May
6.8
7
7
7
7
June
6.3
5
8
7
6
July
6.1
6
6
5
6
August
6.1
6
6
7
6
September
6.1
5
6
6
8
October
6.3
5
7
6
6
November
6.7
8
7
7
7
December
5.6
5
6
6
6
Average
6.4
6.7
5.9
6.8
6.4
6.4
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
2020
January
286°
291°
287°
265°
292°
February
300°
287°
290°
265°
285°
March
308°
321°
311°
278°
261°
April
020°
056°
340°
272°
May
153°
169°
198°
286°
June
137°
258°
228°
152°
July
265°
292°
250°
255°
August
258°
257°
216°
204°
September
147°
268°
242°
280°
October
310°
279°
230°
259°
November
284°
305°
292°
282°
December
267°
039°
284°
289°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.