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
76.4
77
71
90
74
85
February
82.1
90
92
91
71
92
March
82.3
70
86
86
86
84
April
94.9
92
97
88
99
May
97.3
89
98
98
99
June
98.2
99
98
99
99
July
99.3
100
100
100
100
August
99.4
100
100
99
100
September
99.3
99
98
100
100
October
92.1
100
100
81
90
November
65.9
86
68
60
66
December
64.2
73
51
68
41
Average
87.7
78.5
91.7
92.4
87.5
90.1
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.