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
51.1
46
41
54
36
69
February
46.0
39
47
50
68
49
March
43.2
25
35
45
36
44
April
59.8
36
55
64
67
50
May
64.7
60
59
45
82
91
June
60.8
62
64
63
57
62
July
38.6
30
22
42
31
42
August
42.6
26
33
26
49
53
September
67.9
79
53
78
78
October
77.5
78
81
69
73
November
67.7
66
54
73
66
December
54.5
56
67
41
60
Average
55.7
40.1
50.6
51.3
57.7
61.4
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
-8.0
-6
-9
-10
-10
-12
February
-7.8
-6
-9
-8
-7
-9
March
-6.9
-8
-6
-5
-6
-5
April
-1.1
-2
-7
0
0
0
May
5.5
2
3
5
7
10
June
11.2
10
10
13
10
12
July
12.4
11
11
12
11
12
August
11.4
9
12
10
11
13
September
8.8
7
8
8
9
October
3.8
2
3
1
5
November
-2.6
0
-1
-8
1
December
-5.3
-8
-1
-4
-5
Average
2.3
1.4
0.5
2.2
1.3
2.4
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
-13.2
-11
-13
-17
-14
-16
February
-12.6
-11
-14
-13
-14
-16
March
-10.1
-12
-12
-9
-13
-9
April
-6.6
-8
-12
-4
-6
-4
May
1.0
-2
-1
0
2
4
June
6.6
5
6
7
6
7
July
8.7
7
8
8
8
8
August
8.4
7
9
7
8
9
September
5.9
5
6
5
6
October
1.0
0
0
-1
2
November
-6.9
-4
-5
-12
-3
December
-9.0
-13
-5
-9
-10
Average
-2.2
-4.9
-4.5
-2.0
-4.7
-2.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
51.5
51
62
41
71
41
February
57.9
67
60
56
51
53
March
55.7
73
59
56
58
48
April
42.1
60
49
41
36
47
May
28.4
42
32
29
14
14
June
20.5
30
25
16
30
17
July
31.7
41
36
33
33
19
August
31.9
43
33
36
32
17
September
30.1
25
33
29
22
October
32.8
36
33
37
25
November
41.7
39
48
64
41
December
57.3
62
53
65
60
Average
36.8
49.0
40.1
36.9
38.6
30.0
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
19.6
20
22
21
20
19
February
19.5
17
16
20
15
20
March
18.7
22
20
25
17
18
April
16.0
19
16
13
16
17
May
12.3
15
12
14
10
10
June
11.3
13
10
13
10
11
July
10.6
10
10
12
11
10
August
12.8
15
13
14
13
10
September
13.6
13
13
13
16
October
14.2
15
15
14
14
November
17.0
15
19
16
18
December
19.4
19
22
22
17
Average
14.4
15.7
14.0
15.7
13.8
13.8
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
088°
048°
050°
039°
040°
February
093°
046°
084°
081°
064°
March
063°
152°
037°
153°
145°
April
088°
046°
101°
070°
103°
May
049°
044°
010°
061°
094°
June
049°
177°
122°
181°
346°
July
218°
194°
241°
209°
257°
August
199°
204°
342°
235°
019°
September
331°
206°
016°
016°
October
051°
028°
031°
076°
November
070°
061°
042°
127°
December
041°
141°
164°
059°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.