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
83.5
75
85
72
94
84
February
89.9
84
95
93
89
90
March
96.2
97
99
94
96
98
April
97.8
100
98
99
99
May
98.8
97
99
100
100
June
99.0
98
98
100
98
July
98.3
99
100
96
99
August
90.5
94
100
86
99
September
94.3
99
89
100
88
October
91.1
93
81
93
93
November
84.3
93
81
83
83
December
85.1
81
88
87
83
Average
92.2
85.5
94.8
92.0
93.9
93.5
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.