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
93.6
97
81
100
85
99
February
97.0
100
83
100
100
99
March
88.9
100
41
100
100
96
April
81.3
17
97
100
99
May
80.4
5
99
100
99
June
79.8
1
100
100
100
July
71.7
0
63
100
100
August
66.9
0
46
100
99
September
68.1
0
20
100
99
October
77.8
63
37
100
91
November
90.2
100
37
100
98
December
98.9
99
95
99
100
Average
87.3
98.9
38.1
78.4
99.2
98.3
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.