Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 8 km 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
13.3
4
30
9
9
February
31.7
42
41
28
13
March
46.4
57
46
38
47
April
58.7
63
56
58
May
57.6
66
43
66
June
55.7
60
52
56
July
36.4
42
25
44
August
51.8
67
47
41
September
49.3
65
50
31
October
42.9
53
41
35
November
16.4
10
32
6
December
16.8
21
17
8
25
Average
30.4
34.8
48.5
37.7
37.1
24.8
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 5 km or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.