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
81.0
94
77
87
40
92
February
81.8
76
70
82
66
78
March
80.3
84
73
92
56
76
April
86.6
93
86
36
74
May
87.5
85
74
90
96
June
86.5
84
89
92
89
July
84.8
81
91
86
76
August
81.1
68
72
87
September
93.0
100
92
90
94
October
93.1
93
90
93
93
November
84.4
80
80
97
83
December
74.0
75
91
71
37
Average
84.7
82.4
82.9
84.3
79.4
83.5
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
-11.3
-11
-9
-13
-9
-16
February
-9.2
-6
-15
-11
-13
-14
March
-5.5
-6
-3
-4
-6
-7
April
0.8
-5
2
-5
1
May
8.7
7
8
10
11
June
14.8
12
16
13
15
July
15.8
14
16
15
14
August
14.0
13
13
15
September
10.5
9
11
9
10
October
4.3
4
3
2
5
November
-4.8
-2
-3
-11
-1
December
-8.6
-11
-4
-7
-8
Average
1.0
-8.7
-2.6
3.0
1.7
2.1
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
-16.3
-16
-14
-18
-14
-21
February
-15.4
-12
-21
-17
-19
-22
March
-12.4
-13
-11
-10
-15
-12
April
-7.8
-14
-5
-14
-5
May
1.4
0
0
1
2
June
7.8
6
8
7
8
July
10.2
9
10
10
9
August
9.3
8
9
10
September
6.0
6
6
4
5
October
0.0
-1
-1
-2
1
November
-8.7
-6
-7
-15
-6
December
-13.5
-15
-9
-14
-13
Average
-5.3
-14.9
-8.7
-3.4
-5.9
-4.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
22.7
14
38
34
10
28
February
27.3
41
51
25
20
32
March
24.6
31
36
14
37
27
April
18.3
14
12
59
31
May
11.7
17
6
9
6
June
10.9
13
7
18
15
July
18.3
34
19
28
13
August
21.2
30
32
6
September
21.1
29
26
20
19
October
16.6
6
18
20
15
November
23.6
31
30
21
23
December
27.9
45
29
36
13
Average
20.7
31.6
25.5
18.3
23.5
17.4
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
11.0
13
10
12
10
9
February
13.5
14
12
14
13
12
March
11.6
12
12
14
13
13
April
10.5
10
11
18
10
May
8.8
8
10
9
8
June
8.4
8
9
8
9
July
9.2
8
10
10
8
August
9.8
10
11
8
September
10.4
9
10
10
11
October
10.5
7
13
10
10
November
11.8
11
12
8
11
December
12.7
12
13
15
14
Average
10.6
12.8
9.5
11.0
10.3
9.8
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
086°
048°
041°
058°
059°
February
080°
133°
066°
074°
067°
March
099°
178°
045°
171°
191°
April
028°
076°
199°
165°
May
065°
288°
012°
037°
June
153°
147°
197°
256°
July
194°
198°
198°
235°
August
234°
218°
322°
September
178°
151°
229°
322°
October
179°
128°
099°
109°
November
083°
083°
026°
141°
December
085°
161°
170°
074°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.