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
71.8
79
61
80
65
82
February
70.0
56
68
61
79
65
March
81.7
73
81
79
84
84
April
91.5
93
89
93
91
May
90.3
94
90
77
93
June
0
0
0
0
July
90.3
76
85
98
86
August
86.2
80
88
90
91
September
78.2
70
82
90
77
October
63.2
77
65
57
49
November
46.9
56
31
58
55
December
63.0
81
67
57
40
Average
79.9
68.6
79.7
79.9
82.5
81.0
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.