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
70.2
76
46
71
53
76
February
64.2
49
62
65
81
77
March
70.1
58
67
83
61
68
April
85.2
73
91
67
85
May
77.5
70
74
90
77
June
57.7
75
85
80
17
July
52.5
58
65
58
64
August
70.6
78
63
90
88
September
85.4
90
91
93
90
October
88.0
87
91
90
95
November
81.2
82
70
81
86
December
65.4
60
77
36
76
Average
70.4
59.2
71.0
77.3
76.1
72.0
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
-6.5
-4
-4
-7
-5
-13
February
-2.0
-2
-4
-1
-2
-4
March
-2.3
-5
-1
0
-3
-2
April
2.5
-2
3
0
4
May
8.6
7
9
10
11
June
11.4
11
8
11
11
July
13.7
13
13
13
14
August
14.0
13
13
14
15
September
11.2
10
11
9
11
October
5.6
6
6
1
7
November
0.4
2
1
-11
1
December
-3.3
-5
1
-3
-3
Average
3.7
-4.7
4.2
4.9
3.1
4.5
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
-12.3
-9
-11
-15
-10
-18
February
-8.4
-7
-11
-6
-7
-12
March
-8.2
-11
-7
-6
-10
-9
April
-3.2
-9
-2
-6
-1
May
3.0
2
3
3
4
June
6.9
6
5
7
7
July
9.7
9
10
10
10
August
9.9
10
10
10
10
September
6.8
6
7
5
6
October
1.8
1
2
-1
2
November
-4.0
-2
-2
-16
-3
December
-8.3
-12
-5
-8
-7
Average
-2.6
-9.0
-1.1
0.2
-2.3
-1.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
30.6
28
53
33
51
17
February
32.5
51
42
41
21
32
March
27.5
39
50
25
41
27
April
23.0
43
23
17
20
May
18.0
38
5
13
16
June
10.1
20
6
15
4
July
14.9
25
20
19
5
August
16.5
16
26
8
14
September
16.9
23
26
9
18
October
20.8
12
24
16
22
November
27.1
35
36
14
17
December
29.6
22
24
43
34
Average
22.3
40.2
29.6
22.2
19.3
16.5
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
14.6
18
11
16
16
14
February
15.8
17
16
16
16
16
March
13.8
16
19
15
16
14
April
12.7
14
14
15
12
May
11.7
13
13
12
10
June
10.1
11
9
11
9
July
9.5
10
10
11
8
August
11.7
10
13
11
11
September
12.8
12
13
12
13
October
13.8
13
14
15
11
November
13.4
13
15
13
16
December
15.0
16
15
17
14
Average
12.9
16.7
12.5
13.0
12.8
11.6
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
079°
025°
015°
026°
013°
February
081°
075°
098°
094°
083°
March
044°
111°
037°
007°
032°
April
017°
092°
350°
103°
May
054°
330°
086°
106°
June
116°
234°
132°
201°
July
144°
227°
211°
268°
August
175°
259°
196°
333°
September
280°
211°
345°
011°
October
041°
353°
347°
104°
November
053°
033°
004°
120°
December
026°
106°
262°
073°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.