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
57.0
49
37
27
51
84
February
68.5
55
78
65
78
72
March
71.8
73
87
55
74
72
April
64.9
67
60
72
73
May
42.2
38
53
36
55
June
0
0
0
0
July
68.1
81
39
89
87
August
57.3
59
60
72
41
September
51.2
58
32
54
39
October
64.1
61
77
45
66
November
62.3
35
76
52
56
December
0
0
0
0
Average
60.9
63.7
62.1
55.7
62.8
59.9
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
-21.7
-19
-17
-26
-22
-22
February
-21.2
-19
-22
-27
-27
-27
March
-17.1
-22
-17
-18
-20
-16
April
-12.4
-17
-13
-12
-8
May
-2.9
0
-1
-2
-1
June
8.0
10
9
10
8
July
14.5
18
10
16
10
August
10.1
13
12
9
11
September
5.6
6
5
4
4
October
-3.6
-2
-3
-4
-3
November
-10.6
-7
-9
-15
-9
December
-18.9
-17
-10
-22
-19
Average
-7.2
-21.9
-5.7
-6.3
-7.1
-7.9
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.