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
25.9
13
18
34
32
29
February
38.2
32
40
42
26
47
March
54.4
46
52
48
68
55
April
55.2
36
43
76
75
May
62.5
59
42
67
69
June
66.0
67
48
84
63
July
79.2
79
73
84
76
August
78.6
72
82
69
86
September
68.2
59
78
75
62
October
64.7
60
60
64
74
November
45.4
41
40
46
46
December
27.9
16
18
30
48
Average
54.6
30.8
48.6
50.1
62.1
62.3
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
0.5
-2
4
1
1
1
February
0.0
1
0
2
-2
2
March
3.7
5
2
5
4
4
April
6.8
5
4
10
9
May
13.2
16
8
11
13
June
16.5
18
15
20
15
July
21.5
22
23
23
21
August
22.1
23
25
20
21
September
16.7
16
20
16
19
October
10.0
11
15
8
11
November
2.6
2
1
3
3
December
-1.5
2
-2
-2
1
Average
8.5
1.5
10.0
10.1
9.4
9.9
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
-4.2
-6
-2
-4
-2
-3
February
-5.7
-3
-5
-4
-5
-2
March
-2.0
-1
-4
-1
-2
-2
April
-1.8
-1
-2
-1
1
May
4.4
5
2
3
4
June
6.9
5
6
10
7
July
10.6
10
12
12
10
August
11.6
10
13
11
10
September
8.2
6
9
8
10
October
3.4
3
8
2
4
November
-2.7
-2
-5
-1
0
December
-4.2
-2
-6
-6
-3
Average
1.8
-4.6
2.1
2.7
2.5
3.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
30.9
36
19
35
30
56
February
38.6
36
42
28
65
34
March
28.8
34
37
27
21
31
April
28.6
38
47
9
13
May
12.5
4
29
12
16
June
8.0
10
9
9
10
July
1.4
0
2
0
2
August
1.5
5
1
2
1
September
7.0
11
0
12
8
October
15.9
8
18
15
17
November
29.6
21
41
30
32
December
31.9
35
34
49
22
Average
20.4
35.4
20.1
23.8
19.0
18.6
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
3.0
2
2
3
3
4
February
3.7
2
3
3
5
5
March
3.0
2
2
3
4
4
April
3.5
2
3
4
4
May
3.7
3
3
4
4
June
3.8
4
3
3
4
July
4.1
4
3
4
4
August
3.7
3
4
3
4
September
2.9
2
3
3
3
October
2.9
2
3
2
4
November
3.0
2
2
3
3
December
2.9
2
2
2
4
Average
3.3
2.1
2.5
2.9
3.4
4.0
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
347°
230°
298°
262°
253°
February
274°
265°
267°
265°
261°
March
281°
268°
274°
264°
263°
April
258°
272°
263°
264°
May
238°
271°
264°
261°
June
240°
267°
258°
257°
July
240°
238°
234°
251°
August
236°
243°
251°
241°
September
267°
225°
265°
239°
October
260°
251°
293°
262°
November
283°
284°
290°
265°
December
304°
265°
286°
290°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.