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
46.6
57
69
67
58
23
February
52.0
51
46
51
41
37
March
87.8
93
83
88
82
84
April
93.6
92
87
93
95
May
94.9
95
94
93
98
June
88.4
87
80
90
91
July
79.7
83
71
77
85
August
79.3
80
67
86
82
September
85.8
84
74
88
84
October
92.6
95
83
94
94
November
87.4
94
83
87
89
December
60.1
63
66
47
76
Average
77.4
68.0
81.9
75.1
78.5
77.7
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.