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
85.6
89
88
92
76
82
February
83.6
86
88
79
66
93
March
78.3
80
83
81
74
69
April
82.9
79
77
81
86
May
82.0
80
75
68
93
June
0
0
0
0
July
90.0
100
97
85
72
August
92.4
96
91
88
92
September
82.8
86
75
76
86
October
76.0
70
76
63
92
November
82.0
78
82
69
70
December
0
0
0
0
Average
83.3
83.2
84.1
80.5
75.2
84.9
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
-28.5
-28
-29
-29
-23
-27
February
-32.6
-30
-35
-30
-27
-34
March
-26.3
-28
-24
-24
-27
-28
April
-17.5
-16
-17
-15
-17
May
-5.1
-2
-6
-5
-7
June
6.4
7
8
5
7
July
12.6
14
16
10
15
August
10.6
11
10
9
10
September
2.9
5
3
3
3
October
-5.1
-2
-6
0
-4
November
-17.2
-12
-20
-13
-18
December
-23.0
-19
-22
-23
-24
Average
-12.1
-29.5
-8.0
-10.8
-9.3
-11.8
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.