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
88.8
80
82
94
95
92
February
85.0
71
91
88
93
95
March
85.1
74
70
92
95
88
April
94.1
91
90
95
96
May
96.3
90
100
94
96
June
97.3
98
93
99
97
July
95.5
90
93
92
96
August
93.5
94
99
93
100
September
93.3
88
99
95
99
October
95.6
92
97
98
97
November
89.7
96
81
99
88
December
89.6
95
80
93
90
Average
90.6
74.5
89.7
92.8
95.0
94.8
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.