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
59.3
57
24
76
88
59
February
64.3
71
74
43
75
59
March
70.9
54
89
64
76
76
April
69.4
76
75
73
62
May
33.0
30
34
23
37
June
0
0
0
0
July
70.8
88
37
73
98
August
52.9
56
49
67
26
September
48.8
55
29
49
35
October
65.2
60
81
54
69
November
72.3
55
83
73
67
December
0
0
0
0
Average
59.8
60.1
62.7
55.7
62.0
53.7
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
-22.1
-19
-18
-27
-22
-27
February
-22.0
-19
-25
-25
-29
-30
March
-18.3
-21
-16
-19
-22
-17
April
-12.4
-15
-12
-12
-9
May
-1.1
1
-1
-2
-2
June
7.8
11
10
8
9
July
13.6
18
11
14
8
August
9.2
13
11
7
10
September
5.0
6
5
4
3
October
-3.4
-2
-3
-4
-3
November
-11.6
-8
-9
-16
-10
December
-18.5
-15
-12
-24
-19
Average
-8.6
-20.1
-5.8
-6.4
-9.9
-8.9
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.