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
91.1
83
97
90
94
93
February
81.1
92
59
73
94
84
March
92.4
93
96
90
88
85
April
93.3
82
97
99
92
May
98.0
96
100
100
98
June
97.7
96
94
99
99
July
94.3
89
96
98
95
August
92.9
93
89
92
94
September
93.0
93
90
89
97
October
87.7
79
92
88
91
November
76.3
26
93
89
88
December
67.1
0
62
77
87
Average
90.9
89.4
80.2
90.7
93.4
92.8
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
-5.4
-6
-1
-3
-1
-11
February
-3.7
-2
-3
1
-5
-2
March
1.7
3
2
4
-1
0
April
8.5
6
9
9
8
May
14.8
13
16
15
17
June
19.1
17
22
20
19
July
20.7
19
20
20
22
August
18.7
19
17
18
20
September
13.8
13
13
12
14
October
6.8
6
6
6
6
November
-2.9
1
-2
-7
-2
December
-4.4
-6
-8
-7
-1
Average
6.8
-2.2
7.2
8.4
6.7
7.4
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-13.2
-15
-8
-10
-8
-21
February
-12.9
-10
-11
-6
-14
-11
March
-8.1
-5
-8
-3
-14
-11
April
-2.6
-3
-1
-4
-1
May
4.2
4
3
4
5
June
8.7
9
9
8
8
July
11.2
11
11
11
11
August
10.2
11
10
9
10
September
5.8
5
7
3
6
October
-1.9
-3
-1
-1
-2
November
-9.9
-6
-10
-16
-10
December
-11.1
-15
-16
-15
-8
Average
-2.1
-11.5
-2.9
-1.9
-3.0
-2.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
8.1
13
6
12
7
15
February
25.3
16
53
37
18
32
March
9.5
10
5
10
18
22
April
9.1
22
3
5
13
May
8.4
16
1
9
5
June
9.6
22
4
7
12
July
13.4
16
22
10
12
August
18.0
18
26
20
12
September
18.6
15
31
10
19
October
15.7
20
13
16
11
November
12.6
17
12
10
11
December
17.1
0
41
23
18
Average
13.0
12.3
18.0
16.0
12.0
14.1
Precipitation during daylight period
Percentage of observations with observed rain, drizzle, snow or hail. Only observations between sunrise and sunset are taken into account.
Wind speed (knots)
Month
Average
2024
2023
2022
2021
2020
January
4.9
6
3
8
6
4
February
3.5
5
3
3
4
5
March
5.6
5
6
7
3
5
April
4.6
3
5
5
4
May
3.5
4
4
3
3
June
2.4
3
3
2
2
July
1.9
2
3
1
2
August
2.7
3
3
2
3
September
3.2
3
4
2
4
October
4.2
3
5
5
5
November
3.9
4
4
3
6
December
3.6
3
2
3
5
Average
3.7
5.1
3.3
4.0
2.9
3.6
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
2020
January
056°
063°
054°
063°
046°
February
070°
063°
068°
052°
066°
March
070°
060°
061°
067°
045°
April
105°
080°
071°
075°
May
086°
099°
085°
077°
June
079°
161°
050°
071°
July
129°
086°
073°
068°
August
080°
074°
069°
077°
September
075°
073°
071°
068°
October
045°
045°
068°
072°
November
058°
057°
056°
061°
December
057°
067°
053°
065°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.