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
95.3
98
99
71
99
100
February
98.3
98
98
96
96
100
March
99.6
99
100
100
100
100
April
98.8
99
96
99
98
May
98.6
99
99
100
100
June
99.7
99
100
100
100
July
95.0
100
100
100
88
August
93.0
95
97
99
60
September
82.8
100
87
90
1
October
94.1
100
97
98
79
November
88.6
100
96
78
41
December
91.1
96
100
63
85
Average
95.1
98.4
98.7
95.0
94.0
80.3
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.