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
79.3
73
68
87
80
73
February
89.3
71
90
91
93
93
March
90.4
86
92
91
95
92
April
91.9
89
78
95
96
May
96.4
94
89
96
98
June
96.4
98
94
96
96
July
97.1
98
97
90
98
August
94.0
84
94
88
96
September
93.0
87
94
100
99
October
90.8
79
96
95
94
November
86.7
82
90
88
91
December
84.8
90
67
92
82
Average
90.1
76.9
88.1
90.0
92.7
93.2
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
2024
2023
2022
2021
2020
January
-10.2
-10
-10
-12
-6
-10
February
-10.7
-3
-7
-12
-13
-6
March
-2.9
-3
-5
-2
6
1
April
8.6
6
4
13
8
May
19.6
23
16
19
18
June
25.1
27
24
26
26
July
26.4
25
26
28
27
August
25.7
26
26
25
26
September
20.4
23
22
24
20
October
10.0
10
12
15
7
November
-1.4
2
-1
3
2
December
-7.6
-2
-9
-10
-3
Average
7.4
-6.7
9.6
8.4
10.9
9.7
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
-19.4
-18
-18
-23
-15
-17
February
-21.6
-11
-21
-25
-24
-18
March
-12.1
-13
-18
-11
-7
-10
April
-4.1
-4
-4
-4
-5
May
4.4
8
5
2
4
June
11.2
14
11
12
11
July
12.6
10
13
14
15
August
10.7
11
12
11
12
September
6.4
8
7
7
5
October
-2.8
0
0
1
-4
November
-10.3
-7
-9
-8
-10
December
-16.2
-12
-17
-19
-13
Average
-5.7
-14.2
-3.7
-3.0
-3.6
-3.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
33.1
52
25
53
24
35
February
25.9
26
19
33
29
25
March
16.3
27
12
27
9
14
April
12.6
18
30
10
13
May
8.8
8
24
7
9
June
7.5
6
12
7
5
July
3.4
5
6
4
4
August
5.6
9
2
9
4
September
7.5
7
5
1
4
October
12.4
21
7
6
14
November
24.9
16
35
16
16
December
23.8
7
35
33
28
Average
16.1
34.5
12.3
20.4
11.5
12.9
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
9.7
10
8
11
10
10
February
9.9
11
9
11
10
9
March
10.4
11
10
10
11
11
April
11.8
12
14
11
12
May
11.0
11
12
11
11
June
9.9
7
11
10
12
July
8.5
8
9
8
9
August
8.1
8
8
9
8
September
10.2
9
10
10
11
October
11.3
10
11
11
13
November
10.2
10
12
10
11
December
9.5
8
11
11
9
Average
10.1
10.6
9.1
10.8
10.0
10.5
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
304°
289°
312°
285°
297°
February
338°
284°
316°
286°
278°
March
360°
023°
301°
284°
322°
April
042°
035°
008°
313°
May
073°
027°
340°
105°
June
074°
301°
296°
251°
July
300°
322°
036°
250°
August
313°
306°
320°
286°
September
089°
321°
278°
290°
October
353°
314°
347°
288°
November
282°
306°
291°
274°
December
295°
010°
288°
292°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.