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
65.6
55
51
77
60
62
February
82.6
67
92
71
87
90
March
87.3
78
85
84
97
92
April
85.4
82
70
82
93
May
88.8
91
75
89
94
June
92.7
92
92
97
87
July
95.2
97
96
89
99
August
94.0
91
91
88
98
September
86.8
90
86
92
95
October
77.9
67
87
75
92
November
76.9
69
77
87
80
December
65.0
58
51
74
58
Average
82.9
67.4
81.9
81.4
85.6
88.1
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
-10.1
-9
-8
-14
-6
-9
February
-9.5
-2
-7
-13
-12
-7
March
0.3
-1
-2
-1
6
2
April
7.0
6
4
10
7
May
17.5
21
17
18
16
June
23.4
25
23
26
23
July
25.4
24
25
27
27
August
23.9
23
24
24
25
September
17.9
20
19
20
17
October
8.7
10
11
13
5
November
-2.9
0
0
1
2
December
-7.7
-1
-8
-7
-5
Average
6.7
-5.9
9.3
7.7
10.0
8.5
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
-17.1
-14
-14
-23
-13
-15
February
-19.7
-11
-18
-24
-21
-17
March
-10.3
-10
-13
-11
-6
-8
April
-3.2
-3
-4
-1
-4
May
6.5
9
6
6
6
June
13.4
16
12
14
13
July
15.8
14
15
17
17
August
14.7
15
15
16
15
September
10.0
12
10
11
9
October
2.5
4
3
6
-1
November
-8.9
-5
-6
-5
-6
December
-14.4
-7
-14
-16
-13
Average
-2.2
-12.2
0.9
-2.9
0.8
-1.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
48.7
58
54
62
38
50
February
43.0
42
27
63
41
37
March
20.6
35
22
28
8
20
April
20.3
27
44
19
11
May
11.0
4
24
12
6
June
9.7
9
12
6
12
July
5.5
8
9
3
3
August
7.5
11
12
8
4
September
13.5
7
15
7
8
October
25.7
27
19
15
26
November
43.5
32
48
30
29
December
46.8
24
59
48
46
Average
24.6
43.8
19.4
29.6
17.4
18.5
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
7.3
7
7
9
7
7
February
8.1
8
8
9
8
8
March
8.5
10
9
8
9
9
April
8.8
9
9
9
9
May
8.5
10
9
8
8
June
8.2
7
10
8
9
July
7.7
7
8
7
8
August
7.6
7
7
9
8
September
8.2
8
8
8
9
October
8.2
7
9
8
8
November
8.4
9
9
8
9
December
7.3
7
8
8
7
Average
8.1
8.2
7.9
8.4
8.0
8.2
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
234°
220°
250°
210°
209°
February
260°
237°
252°
239°
255°
March
316°
001°
277°
198°
216°
April
049°
058°
006°
278°
May
126°
185°
221°
249°
June
142°
252°
250°
197°
July
280°
263°
235°
230°
August
231°
233°
219°
233°
September
144°
211°
225°
263°
October
350°
243°
170°
252°
November
251°
226°
248°
225°
December
208°
122°
226°
233°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.