Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 8 km 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
43.2
50
62
18
67
43
February
63.0
61
75
77
67
76
March
75.0
80
77
87
72
86
April
84.0
94
97
80
91
May
86.7
96
88
85
85
June
90.6
94
95
93
89
July
94.3
98
97
93
86
August
97.7
99
100
92
99
September
95.6
97
99
100
92
October
85.1
83
94
85
78
November
71.7
89
80
81
72
December
58.0
73
87
69
49
Average
77.7
63.8
86.9
85.7
82.3
79.6
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 5 km or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.