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
69.1
79
57
73
55
69
February
70.5
52
71
80
64
78
March
68.1
68
48
81
77
67
April
64.9
58
55
56
84
May
71.5
66
73
80
79
June
69.9
41
68
88
74
July
80.4
78
86
79
78
August
82.2
77
86
84
80
September
78.9
64
77
79
91
October
76.5
68
75
63
84
November
71.9
69
67
71
81
December
66.5
72
39
71
59
Average
72.4
65.6
63.3
73.1
73.5
77.6
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
-2.5
-3
0
0
-1
-4
February
-3.8
0
-5
-1
-2
-2
March
0.7
3
0
1
2
-1
April
5.2
5
6
8
4
May
10.8
11
13
12
11
June
17.7
16
19
21
20
July
22.6
25
23
22
21
August
22.5
21
24
23
23
September
17.4
18
18
19
19
October
11.3
12
15
9
12
November
4.8
3
4
8
6
December
0.7
2
2
0
3
Average
8.1
0.0
9.1
10.6
10.0
9.4
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
-8.0
-9
-6
-8
-4
-10
February
-10.3
-5
-13
-10
-7
-10
March
-6.3
-3
-5
-6
-5
-8
April
-2.3
-2
-1
1
-2
May
1.7
2
2
3
3
June
7.6
6
9
9
10
July
12.7
16
14
12
11
August
13.3
13
15
13
13
September
9.1
10
11
10
10
October
4.2
5
6
4
4
November
-2.8
-3
-2
2
-1
December
-5.2
-4
-3
-6
-2
Average
0.6
-6.1
1.7
2.5
2.6
1.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
42.8
32
53
46
46
40
February
44.2
39
47
41
60
44
March
40.5
40
54
33
34
40
April
35.7
47
38
46
15
May
29.5
38
24
25
29
June
26.6
50
26
8
23
July
17.4
23
17
21
17
August
16.0
26
15
10
18
September
22.5
28
24
19
11
October
22.2
27
15
31
17
November
34.6
35
47
30
27
December
41.0
35
36
44
42
Average
30.5
37.4
38.4
28.5
28.7
25.4
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
13.0
13
12
14
12
12
February
13.8
14
14
14
13
15
March
13.9
13
16
14
13
15
April
13.7
15
14
15
13
May
12.1
13
12
12
13
June
10.9
11
13
11
11
July
9.7
9
10
10
9
August
9.7
9
9
11
10
September
11.0
10
12
11
12
October
11.2
10
11
13
12
November
13.1
12
13
13
13
December
13.3
14
13
15
12
Average
12.1
13.2
11.8
12.1
12.2
12.0
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
274°
294°
211°
337°
290°
February
312°
320°
250°
311°
248°
March
137°
359°
241°
246°
286°
April
350°
009°
074°
258°
May
325°
319°
277°
256°
June
014°
263°
220°
193°
July
206°
224°
214°
196°
August
182°
207°
258°
236°
September
258°
264°
235°
231°
October
264°
238°
348°
227°
November
282°
271°
187°
234°
December
264°
061°
263°
192°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.