Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 5 mi 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
87.8
73
98
64
98
90
February
93.4
97
97
93
90
91
March
98.6
100
100
96
99
98
April
98.7
100
98
100
99
May
98.8
100
98
99
99
June
98.5
99
97
99
99
July
99.3
100
99
100
100
August
98.9
100
100
99
99
September
94.7
100
100
97
74
October
94.5
95
97
98
88
November
94.1
95
85
95
95
December
91.3
83
96
93
94
Average
95.5
90.0
97.5
94.3
97.6
94.2
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 3⅛ mi or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.