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
67.5
62
61
58
75
83
February
71.4
55
74
62
74
82
March
72.9
76
81
74
74
70
April
74.9
80
75
68
87
May
75.3
69
88
58
75
June
0
0
0
0
July
83.3
80
75
64
85
August
83.0
75
86
73
90
September
77.0
62
67
74
87
October
70.9
62
67
67
65
November
71.3
61
75
79
62
December
63.6
50
50
100
100
Average
74.9
67.1
71.6
74.7
69.9
80.0
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
-26.8
-22
-31
-25
-19
-27
February
-29.1
-21
-37
-31
-23
-32
March
-22.3
-19
-18
-21
-26
-23
April
-14.9
-13
-14
-11
-14
May
-4.3
-3
-3
-4
-4
June
4.5
3
8
3
3
July
10.7
10
16
8
13
August
8.8
9
10
7
10
September
2.9
3
4
2
2
October
-4.9
-2
-3
1
-2
November
-14.6
-7
-17
-10
-16
December
-17.0
-14
-15
-18
-15
Average
-10.2
-21.6
-9.8
-8.9
-8.5
-9.4
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.