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
88.5
88
86
91
88
88
February
84.6
94
93
91
78
88
March
91.8
92
91
99
95
86
April
92.5
90
97
90
87
May
95.4
95
98
93
100
June
95.9
97
99
96
96
July
96.2
96
99
91
96
August
98.1
98
97
98
100
September
95.0
99
94
97
98
October
91.9
95
97
94
90
November
89.1
91
85
97
86
December
88.4
93
82
85
95
Average
92.3
91.3
93.5
94.8
92.1
92.5
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.