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
97.6
95
99
98
98
98
February
98.0
99
98
97
96
99
March
98.1
95
98
98
99
99
April
98.6
98
98
100
100
May
97.0
94
97
99
98
June
95.8
91
96
99
92
July
98.3
96
100
97
100
August
98.1
97
100
99
99
September
98.7
99
99
99
98
October
98.5
96
99
100
99
November
97.8
95
99
99
95
December
97.6
94
97
99
98
Average
97.8
96.3
96.0
98.2
98.6
97.8
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.