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
64.8
55
39
85
66
68
February
85.7
76
90
76
88
91
March
86.9
77
84
76
98
90
April
84.6
75
73
82
93
May
90.3
94
77
91
90
June
94.2
94
91
96
94
July
94.9
93
92
96
98
August
93.3
88
92
90
95
September
87.6
85
83
94
95
October
82.4
76
83
78
95
November
81.8
79
79
86
81
December
69.7
57
69
75
68
Average
84.8
69.4
79.9
81.6
87.7
89.5
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
-10.3
-9
-8
-15
-6
-8
February
-7.0
-2
-6
-13
-8
-5
March
0.8
-1
-2
-1
6
2
April
7.0
6
4
9
7
May
17.6
21
17
18
17
June
23.2
25
22
25
24
July
25.3
23
24
27
27
August
23.6
23
24
25
24
September
17.9
20
18
20
16
October
8.5
9
11
13
5
November
-2.6
0
0
1
1
December
-7.6
-1
-7
-7
-6
Average
6.8
-4.0
9.2
7.6
10.1
8.6
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
-18.7
-15
-14
-24
-14
-15
February
-19.5
-12
-18
-24
-22
-18
March
-11.6
-11
-13
-11
-7
-9
April
-4.3
-4
-4
-2
-4
May
5.8
8
6
6
5
June
12.4
15
11
14
12
July
14.7
13
14
16
16
August
13.7
14
14
15
14
September
9.2
11
9
11
7
October
2.2
4
3
6
-2
November
-8.5
-6
-6
-5
-6
December
-15.6
-7
-15
-16
-13
Average
-3.5
-13.5
0.1
-2.3
0.2
-1.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
32.6
46
35
37
29
28
February
28.2
39
22
47
16
22
March
21.4
39
26
39
8
19
April
20.6
30
47
12
12
May
10.7
6
26
7
7
June
8.0
12
16
3
8
July
7.2
14
14
3
3
August
5.9
10
11
5
7
September
9.3
10
10
7
6
October
22.6
32
30
11
19
November
34.8
31
48
30
27
December
33.4
29
53
39
37
Average
19.5
41.0
21.0
30.3
12.5
14.3
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
7.2
7
6
9
7
7
February
8.5
8
8
9
9
8
March
8.7
10
8
8
9
9
April
9.0
9
9
8
9
May
8.6
9
9
8
8
June
8.2
7
10
8
9
July
7.6
7
7
7
8
August
7.2
7
8
9
8
September
7.9
7
8
8
9
October
8.3
7
9
8
8
November
8.4
9
8
9
8
December
7.4
7
8
8
7
Average
8.1
8.3
7.5
8.5
8.1
8.3
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
246°
242°
243°
215°
218°
February
263°
241°
245°
243°
254°
March
303°
011°
287°
211°
224°
April
039°
046°
028°
257°
May
122°
166°
217°
242°
June
128°
250°
246°
204°
July
267°
260°
246°
233°
August
222°
220°
223°
222°
September
132°
232°
224°
249°
October
300°
253°
182°
239°
November
247°
227°
250°
238°
December
234°
120°
230°
234°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.