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
85.4
87
83
76
90
84
February
91.2
79
97
97
99
98
March
95.2
92
100
94
100
94
April
96.4
93
99
95
99
May
99.1
99
99
99
100
June
99.0
99
99
100
99
July
98.1
94
100
96
100
August
93.1
87
100
88
100
September
93.8
99
95
100
83
October
97.4
99
99
99
95
November
88.9
86
78
100
92
December
84.1
73
83
86
83
Average
93.3
86.5
92.7
94.2
96.0
94.5
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.