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
70.5
72
60
62
87
72
February
73.9
79
68
65
84
74
March
73.6
52
74
64
80
88
April
77.5
83
66
84
89
May
76.6
87
64
83
75
June
65.7
36
71
66
66
July
60.3
36
60
61
69
August
65.2
63
45
65
73
September
72.0
58
70
80
68
October
82.5
82
76
90
81
November
82.9
84
82
88
75
December
75.5
63
77
88
76
Average
72.0
65.9
63.8
65.5
78.2
75.3
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
2.5
2
5
2
2
3
February
2.6
2
3
3
2
3
March
4.5
7
5
6
6
5
April
9.0
11
9
10
8
May
13.5
14
15
14
13
June
18.0
18
18
19
19
July
21.9
23
22
21
22
August
22.2
21
23
23
22
September
19.3
20
19
20
19
October
15.1
16
16
16
14
November
9.2
7
11
10
11
December
4.7
6
6
6
7
Average
10.9
3.4
12.3
12.7
12.3
12.1
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
-4.0
-4
-1
-7
-3
-4
February
-5.6
-4
-6
-5
-4
-3
March
-2.2
0
-1
-1
-2
-1
April
2.4
3
3
3
1
May
6.2
6
7
6
6
June
10.7
11
11
12
11
July
14.6
16
15
14
15
August
14.9
14
16
16
15
September
12.1
13
13
14
11
October
8.2
10
9
9
7
November
2.6
1
4
3
4
December
-2.6
0
-1
-1
1
Average
4.1
-3.5
5.5
5.5
5.6
5.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
36.3
31
46
55
21
34
February
31.1
35
36
37
19
36
March
26.2
43
29
31
21
13
April
18.0
11
28
14
19
May
12.1
7
11
14
8
June
13.9
27
18
6
7
July
8.2
16
8
12
6
August
9.1
20
12
6
4
September
7.8
8
9
9
8
October
12.5
17
14
11
6
November
19.5
26
15
18
17
December
29.7
33
29
15
29
Average
19.5
37.0
21.9
20.7
13.3
14.0
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
12.1
12
11
13
11
12
February
12.6
13
13
13
12
11
March
13.5
14
13
12
14
14
April
12.2
11
13
13
13
May
10.9
12
11
11
13
June
9.4
9
9
9
9
July
8.0
8
9
8
8
August
8.1
9
8
8
9
September
9.6
9
10
10
10
October
10.1
9
9
9
11
November
12.1
11
14
11
11
December
11.8
11
13
13
12
Average
11.0
12.9
10.1
10.8
10.6
10.9
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
345°
353°
352°
355°
313°
February
324°
334°
273°
322°
286°
March
275°
348°
288°
288°
328°
April
279°
301°
315°
304°
May
267°
220°
268°
251°
June
195°
231°
231°
227°
July
201°
236°
224°
222°
August
232°
220°
219°
250°
September
251°
283°
226°
222°
October
260°
167°
336°
276°
November
307°
278°
312°
258°
December
349°
018°
321°
291°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.