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
99.7
100
100
99
100
100
February
100.0
100
100
100
100
100
March
100.0
100
100
100
100
100
April
99.7
100
100
98
99
May
99.4
99
99
100
100
June
99.3
99
99
99
100
July
99.8
100
100
100
100
August
99.2
99
98
100
100
September
99.8
100
100
100
100
October
98.6
100
95
98
100
November
99.3
99
100
100
99
December
99.7
100
99
99
100
Average
99.6
100.0
99.6
99.1
99.5
99.8
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.