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
84.5
78
82
87
89
89
February
85.6
89
89
69
88
91
March
85.7
87
84
75
92
87
April
90.1
94
92
98
93
May
94.5
99
89
97
95
June
94.5
88
96
95
96
July
96.3
88
100
98
95
August
96.9
90
100
100
97
September
94.4
89
97
93
95
October
89.7
80
94
89
90
November
84.8
85
79
93
90
December
84.2
84
80
80
87
Average
90.2
84.8
88.0
89.2
93.3
92.6
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
-9.1
-7
-7
-14
-7
-8
February
-7.1
-4
-8
-9
-7
-5
March
-1.3
2
0
-3
2
-1
April
6.4
9
6
11
5
May
15.9
17
18
16
15
June
21.5
21
21
22
23
July
24.4
25
24
23
25
August
22.6
21
23
26
22
September
18.2
20
18
18
18
October
10.9
14
14
13
8
November
1.3
1
4
3
5
December
-6.6
-2
-2
-5
-3
Average
6.9
-3.2
9.3
8.7
9.6
8.6
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
-18.2
-15
-16
-25
-13
-16
February
-17.3
-14
-18
-20
-16
-15
March
-10.1
-7
-9
-10
-9
-11
April
-3.6
-2
-2
-1
-4
May
4.5
5
5
6
4
June
11.2
12
11
13
12
July
14.8
16
14
13
17
August
13.7
13
14
16
13
September
9.1
11
9
10
8
October
3.4
7
5
5
1
November
-6.9
-6
-2
-3
-3
December
-14.8
-10
-8
-15
-11
Average
-3.9
-12.1
0.4
-1.6
0.6
-1.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
40.9
42
36
32
39
38
February
34.3
31
31
45
30
43
March
27.0
21
28
40
18
24
April
19.7
19
18
8
20
May
12.6
10
16
10
16
June
13.5
16
21
13
8
July
7.6
15
10
4
8
August
10.8
19
11
3
13
September
11.1
11
7
14
13
October
17.3
27
11
9
23
November
28.5
30
32
20
18
December
37.2
34
35
31
28
Average
21.2
30.6
21.4
21.5
14.8
19.4
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
7.5
7
7
8
7
6
February
8.0
8
8
9
7
9
March
9.0
9
8
9
11
8
April
8.2
8
9
8
8
May
8.1
10
7
8
9
June
6.9
5
7
8
7
July
6.6
5
8
7
5
August
6.6
6
6
7
7
September
6.8
5
8
7
9
October
7.1
7
7
5
7
November
8.3
7
9
8
9
December
7.5
7
9
8
8
Average
7.6
8.0
6.8
7.8
7.5
7.6
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
270°
300°
280°
307°
295°
February
281°
284°
290°
297°
251°
March
310°
306°
294°
285°
312°
April
286°
311°
338°
289°
May
323°
299°
303°
299°
June
033°
237°
259°
256°
July
240°
260°
294°
278°
August
285°
263°
240°
283°
September
286°
290°
274°
236°
October
252°
232°
326°
263°
November
261°
245°
258°
258°
December
289°
280°
275°
260°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.