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
50.8
38
67
22
70
55
February
53.1
56
34
36
70
61
March
94.0
96
98
98
89
97
April
97.6
99
97
99
96
May
99.8
100
100
100
100
June
99.5
100
100
99
99
July
99.1
100
100
100
100
August
98.6
97
100
99
100
September
98.0
98
100
100
97
October
93.6
90
100
91
96
November
84.3
67
82
96
91
December
51.1
49
39
54
73
Average
86.1
67.2
87.5
87.4
91.5
91.4
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.