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
78.5
81
75
75
67
98
February
80.1
74
85
70
80
93
March
70.6
81
49
60
81
83
April
67.0
64
44
73
90
May
64.7
67
77
55
59
June
70.9
53
72
85
77
July
79.8
83
66
87
88
August
78.5
71
79
92
79
September
88.9
85
86
84
96
October
86.9
75
93
84
89
November
85.0
93
82
85
89
December
78.7
82
69
84
75
Average
78.9
78.5
70.8
70.9
79.5
83.1
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
-8.4
-6
-7
-10
-4
-10
February
-9.6
-4
-11
-11
-5
-9
March
-3.6
0
-1
-4
-2
-3
April
2.7
2
2
5
3
May
6.5
7
8
7
6
June
14.0
13
15
17
14
July
20.3
24
17
20
21
August
18.9
18
20
20
20
September
14.3
15
17
14
15
October
8.1
10
11
7
8
November
0.6
1
-1
3
1
December
-3.6
-1
-1
-4
0
Average
3.6
-4.6
5.8
5.6
6.6
5.3
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
-16.3
-15
-16
-20
-9
-17
February
-18.7
-11
-22
-22
-11
-18
March
-11.3
-8
-7
-13
-11
-13
April
-4.5
-4
-2
-1
-4
May
0.2
0
0
1
1
June
4.7
3
5
6
5
July
10.0
13
8
10
10
August
10.0
10
11
10
10
September
5.9
6
7
7
6
October
2.3
4
3
2
2
November
-5.5
-5
-6
-2
-6
December
-9.5
-6
-6
-10
-6
Average
-4.2
-12.6
-2.1
-3.2
-1.3
-3.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
35.7
43
40
42
44
11
February
35.8
55
35
39
31
16
March
36.1
31
52
43
28
24
April
36.2
39
54
25
24
May
32.6
43
29
35
24
June
25.8
33
26
21
21
July
14.3
12
26
8
10
August
19.5
27
27
10
14
September
19.3
24
23
22
12
October
21.4
29
20
22
17
November
28.6
25
42
19
21
December
36.8
49
35
29
36
Average
28.2
42.0
34.0
33.7
23.3
18.7
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
10.9
12
9
11
12
10
February
10.6
10
11
11
10
10
March
11.1
11
11
13
10
11
April
10.2
9
12
8
9
May
9.5
10
11
10
7
June
9.1
9
11
9
8
July
7.3
7
7
7
8
August
7.4
7
7
8
8
September
9.5
8
9
10
10
October
9.8
10
9
9
11
November
11.0
12
11
10
12
December
11.4
13
10
12
11
Average
9.9
10.8
9.4
10.1
9.2
9.3
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
275°
281°
257°
328°
265°
February
270°
259°
280°
322°
263°
March
346°
001°
343°
284°
288°
April
348°
356°
028°
270°
May
336°
329°
355°
002°
June
009°
341°
260°
319°
July
243°
005°
276°
281°
August
002°
244°
304°
040°
September
356°
269°
313°
235°
October
312°
243°
339°
249°
November
266°
305°
244°
261°
December
298°
042°
267°
279°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.