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
54.1
53
46
70
47
71
February
75.6
85
76
93
74
73
March
85.7
89
81
92
88
92
April
89.1
93
96
89
81
May
86.0
87
87
80
93
June
84.3
88
88
89
77
July
93.8
98
98
94
85
August
98.0
98
100
97
99
September
87.8
94
77
97
85
October
78.7
82
89
82
70
November
65.7
79
64
48
80
December
52.2
56
66
63
52
Average
79.4
75.7
81.9
86.0
79.8
80.4
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.