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
75.0
65
82
85
79
80
February
79.2
81
78
86
80
81
March
88.4
82
93
97
91
90
April
93.2
93
93
99
93
May
94.0
90
94
96
92
June
98.5
98
99
99
98
July
95.1
92
97
97
95
August
94.1
97
97
97
90
September
89.7
81
91
88
94
October
80.7
87
74
76
81
November
61.6
57
54
64
72
December
72.2
80
79
75
79
Average
87.0
77.3
88.5
90.6
90.2
89.6
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.