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
30.3
4
54
48
30
32
February
49.1
68
67
60
11
32
March
64.7
83
73
82
57
44
April
82.7
92
97
83
89
May
83.9
85
93
86
96
June
74.5
94
86
56
73
July
65.9
86
68
52
70
August
62.6
93
73
58
53
September
51.3
72
85
52
36
October
41.3
64
66
54
24
November
29.1
18
51
15
19
December
23.0
18
20
26
23
Average
56.1
52.6
70.3
72.4
50.7
51.1
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.