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
96.0
94
100
92
99
98
February
96.5
98
98
92
99
96
March
98.1
98
98
97
100
99
April
96.8
87
99
100
99
May
97.7
99
98
98
94
June
96.2
96
91
98
99
July
98.1
98
98
98
99
August
98.3
98
99
100
97
September
97.5
98
96
99
97
October
97.5
99
95
98
97
November
95.9
95
90
95
96
December
96.9
96
95
98
98
Average
97.1
96.4
96.6
95.2
98.4
97.4
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.