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
73.8
75
71
64
70
69
February
86.4
79
78
86
86
91
March
90.9
89
86
93
90
95
April
89.7
85
93
87
92
May
91.3
88
92
95
100
June
95.0
96
95
89
98
July
94.6
92
96
87
96
August
91.0
79
93
89
96
September
90.1
87
87
88
94
October
91.4
88
92
87
96
November
79.6
83
82
67
83
December
75.6
72
72
68
84
Average
88.1
81.6
84.6
89.1
85.4
92.5
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.