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
70.2
78
81
55
63
69
February
82.7
81
85
88
80
92
March
92.2
94
95
93
93
95
April
94.8
93
90
96
98
May
94.8
93
98
96
98
June
95.6
96
97
90
95
July
96.6
98
99
89
99
August
96.7
94
99
94
98
September
93.7
97
93
93
93
October
86.8
93
82
85
90
November
73.3
88
76
58
77
December
66.6
69
49
57
73
Average
88.7
85.6
91.5
88.9
85.4
91.7
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.