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
74.2
67
64
75
68
71
February
78.3
71
68
71
55
90
March
78.0
78
81
71
75
67
April
84.0
85
72
84
92
May
82.6
89
80
58
94
June
0
0
0
0
July
91.2
100
97
66
88
August
89.7
89
89
89
94
September
78.2
78
74
82
87
October
67.6
51
67
83
63
November
79.0
71
81
70
93
December
60.0
25
40
100
100
Average
79.7
73.5
77.1
76.1
74.7
84.4
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
-27.2
-25
-29
-28
-19
-26
February
-31.6
-28
-35
-32
-26
-32
March
-25.8
-23
-23
-24
-26
-26
April
-17.7
-15
-17
-14
-18
May
-5.6
-1
-5
-5
-6
June
7.3
7
10
5
8
July
13.3
14
17
10
17
August
11.1
12
9
8
12
September
3.2
5
3
3
3
October
-5.7
-2
-5
1
-3
November
-16.4
-10
-18
-12
-17
December
-23.3
-19
-21
-23
-24
Average
-12.7
-26.8
-8.4
-10.9
-9.6
-11.5
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.