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
85.8
72
75
92
96
93
February
89.8
94
85
94
92
92
March
88.1
84
84
76
99
90
April
92.4
87
98
89
96
May
93.4
97
95
96
96
June
95.7
90
98
93
98
July
96.2
94
93
95
100
August
98.2
99
97
99
97
September
97.2
100
93
99
96
October
94.2
97
92
90
98
November
92.1
99
77
94
95
December
86.3
77
86
89
90
Average
91.9
82.4
90.2
91.0
94.5
95.2
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.