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
41.0
34
33
43
27
29
February
70.9
48
78
71
84
64
March
85.9
75
71
90
89
95
April
87.4
70
86
98
87
82
May
83.9
89
82
72
97
June
71.3
57
86
66
95
July
45.1
19
58
46
65
August
33.9
17
42
34
29
September
45.5
45
63
14
40
October
80.1
83
88
75
62
November
39.9
7
67
32
24
December
32.8
19
36
19
39
Average
59.9
57.5
50.5
69.5
53.1
56.1
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.