Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 5 mi 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
71.5
71
72
72
86
February
85.3
75
87
92
87
100
March
89.2
87
86
88
97
April
92.3
87
97
94
May
98.6
98
98
99
June
99.6
99
100
100
0
July
99.5
100
100
100
August
98.9
99
99
100
September
99.8
100
100
October
97.7
98
97
November
86.0
90
82
December
74.3
68
84
75
Average
93.0
78.0
91.2
93.6
95.8
100.0
Marginal VFR conditions or better during daylight period
Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 3⅛ mi or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.
Maximum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-5.2
-3
-6
-6
-1
February
-4.6
-1
-7
-4
-1
-5
March
1.5
2
-3
3
5
April
8.0
2
10
13
May
16.7
17
16
18
June
23.3
20
24
28
9
July
27.8
29
31
23
August
27.1
26
29
23
September
23.2
22
25
October
14.6
15
15
November
2.1
5
-1
December
-4.9
-2
-5
-3
Average
8.7
-1.4
9.9
11.8
12.7
-2.2
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.