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
84.3
95
94
88
97
56
February
88.6
96
94
91
94
96
March
84.5
97
94
92
22
95
April
83.0
99
95
97
0
96
May
79.1
95
96
0
96
June
76.1
95
95
0
95
July
93.5
97
99
76
98
August
90.1
97
97
73
99
September
68.1
95
95
76
95
October
82.4
95
97
96
97
November
89.2
91
89
96
94
December
80.6
97
92
77
95
Average
84.6
96.7
94.8
94.0
56.0
93.0
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.