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
72.2
60
62
64
84
February
66.2
56
48
60
66
March
67.6
56
70
61
68
April
69.1
55
68
63
May
61.9
53
47
56
67
June
43.2
40
38
37
50
July
26.1
13
27
20
33
August
41.5
38
17
55
51
September
68.9
49
57
80
91
October
68.7
32
58
82
88
November
59.5
58
0
87
88
December
73.4
58
72
47
87
Average
56.8
57.2
44.9
36.3
57.8
66.3
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
0.2
0
0
0
-2
February
1.2
-1
-1
3
0
March
1.4
-2
4
2
2
April
3.8
3
4
4
May
6.9
11
5
6
8
June
10.0
13
10
9
11
July
10.8
13
11
10
12
August
10.7
15
8
12
13
September
8.0
0
10
10
4
October
5.7
4
7
3
5
November
4.0
5
5
2
4
December
1.3
1
3
2
2
Average
5.0
-1.1
6.0
7.4
5.5
5.0
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
-4.8
-3
-3
-4
-6
February
-3.9
-4
-5
0
-4
March
-3.6
-6
0
-1
-2
April
-1.9
-1
0
0
May
2.0
0
1
3
3
June
5.0
1
6
6
6
July
6.7
6
7
7
8
August
7.1
7
5
8
9
September
5.2
0
6
7
2
October
2.4
2
3
2
1
November
0.7
1
2
-2
1
December
-3.7
-3
1
0
-2
Average
1.2
-5.5
0.6
4.0
2.2
1.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
33.4
46
37
39
36
February
36.6
49
47
28
33
March
24.5
50
41
21
11
April
19.7
41
13
17
May
13.4
20
3
13
8
June
8.6
6
13
11
6
July
11.5
13
11
12
5
August
7.9
9
4
10
12
September
12.7
0
16
12
8
October
19.0
12
23
17
14
November
24.8
38
17
29
21
December
28.6
51
17
2
20
Average
20.6
48.5
23.7
12.4
16.4
13.7
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
17.9
21
15
19
18
February
19.0
18
21
17
18
March
15.5
17
17
14
15
April
14.8
13
17
15
May
12.5
15
0
15
13
June
9.7
12
0
12
11
July
7.5
9
0
10
9
August
10.6
12
9
10
10
September
12.3
6
15
12
13
October
13.2
7
16
15
13
November
16.2
18
17
15
19
December
16.8
18
20
8
18
Average
13.4
18.7
12.9
7.8
13.6
13.6
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
044°
073°
038°
072°
February
254°
360°
094°
085°
March
041°
253°
233°
169°
April
050°
028°
134°
May
331°
360°
075°
095°
June
090°
360°
064°
010°
July
198°
360°
199°
170°
August
176°
321°
180°
180°
September
241°
252°
293°
333°
October
137°
295°
278°
246°
November
297°
069°
018°
255°
December
349°
149°
230°
100°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.