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
81.9
93
56
78
81
94
February
69.6
64
69
53
68
71
March
81.3
81
78
84
74
80
April
83.8
71
74
95
90
78
May
92.8
83
99
94
92
June
84.8
83
81
88
94
July
83.9
72
78
85
86
August
83.4
83
78
91
88
September
92.0
90
85
92
98
October
91.0
96
90
86
88
November
87.5
91
84
93
82
December
78.9
76
84
66
77
Average
84.3
76.0
79.7
83.1
85.4
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
-5.0
-4
-2
-4
-3
-12
February
-3.6
-2
-3
-2
-3
-5
March
-1.7
-1
0
1
-1
0
April
4.9
3
2
5
5
6
May
11.6
9
14
13
14
June
16.0
14
19
15
16
July
17.9
17
17
17
19
August
16.9
17
16
17
18
September
12.9
12
12
11
13
October
7.0
7
6
5
7
November
-1.8
1
0
-9
1
December
-4.1
-6
-4
-4
-3
Average
5.5
-1.1
5.4
7.0
5.2
6.1
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
-12.6
-10
-8
-13
-9
-20
February
-9.1
-7
-13
-7
-10
-13
March
-9.9
-10
-9
-6
-12
-9
April
-3.6
-4
-7
-2
-3
-1
May
3.2
3
4
3
4
June
7.8
7
9
7
7
July
10.1
10
10
10
10
August
9.5
10
10
9
9
September
5.7
5
6
4
6
October
0.8
-1
0
-1
2
November
-7.4
-5
-6
-18
-6
December
-10.1
-13
-10
-11
-9
Average
-2.4
-8.2
-2.3
-1.7
-3.5
-2.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
21.7
11
51
25
20
10
February
27.4
41
24
37
19
33
March
18.2
23
15
21
18
20
April
21.6
28
29
17
19
20
May
20.6
37
4
16
14
June
16.4
29
7
23
12
July
18.0
31
20
22
13
August
19.5
23
24
13
11
September
19.9
22
33
21
17
October
21.9
18
27
24
21
November
19.6
18
29
12
20
December
26.6
32
13
29
29
Average
20.8
26.3
27.4
20.4
19.4
17.2
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
9.3
11
9
11
9
9
February
8.9
10
8
9
9
10
March
7.9
8
8
11
7
7
April
7.8
8
8
8
9
7
May
8.1
9
8
7
7
June
6.7
8
6
8
7
July
6.0
7
7
7
5
August
7.0
7
8
6
6
September
7.6
7
8
8
9
October
8.2
8
9
8
7
November
7.7
7
9
6
8
December
8.4
8
8
7
10
Average
7.7
8.8
7.7
8.1
7.3
7.4
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
036°
016°
009°
014°
003°
February
078°
012°
042°
024°
032°
March
039°
352°
021°
181°
016°
April
069°
029°
069°
037°
060°
May
081°
017°
074°
095°
June
127°
134°
131°
144°
July
137°
148°
169°
194°
August
167°
230°
190°
179°
September
266°
185°
021°
009°
October
023°
004°
008°
050°
November
016°
009°
006°
195°
December
360°
040°
257°
038°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.