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
86.2
95
80
73
83
95
February
89.2
83
93
88
93
100
March
83.3
77
96
83
92
90
April
81.7
84
84
71
94
May
73.3
66
85
54
79
June
0
0
0
0
July
81.7
100
76
38
82
August
81.6
73
88
72
94
September
71.6
63
55
73
87
October
68.5
66
78
58
54
November
76.7
70
88
74
84
December
0
0
0
0
Average
79.4
80.9
77.9
79.8
72.3
86.3
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
-27.4
-24
-30
-28
-18
-29
February
-31.6
-27
-37
-32
-23
-32
March
-25.9
-22
-21
-23
-27
-27
April
-15.0
-14
-16
-12
-15
May
-5.3
-4
-6
-5
-6
June
4.5
2
5
3
4
July
10.4
11
14
8
13
August
8.4
9
9
7
9
September
1.6
2
2
0
1
October
-5.2
-3
-5
0
-3
November
-16.1
-10
-19
-13
-17
December
-21.8
-17
-18
-20
-18
Average
-12.4
-25.7
-10.7
-10.0
-8.1
-11.7
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.