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
84.2
84
81
82
81
93
February
87.7
83
88
87
86
98
March
85.2
87
78
84
84
90
April
86.2
91
76
76
89
May
90.1
86
96
89
84
June
88.8
84
95
93
80
July
92.8
96
85
99
96
August
92.8
96
91
94
95
September
93.5
82
89
95
93
October
92.2
87
100
94
91
November
82.6
91
93
75
85
December
82.6
90
79
85
69
Average
88.4
84.7
87.7
88.4
88.5
89.0
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
-11.8
-7
-11
-13
-6
-11
February
-10.3
-5
-12
-13
-6
-9
March
-3.7
0
-1
-4
-1
-4
April
3.7
5
3
5
4
May
10.1
11
11
10
10
June
16.5
18
19
18
16
July
22.3
25
20
24
24
August
21.0
20
22
22
22
September
15.6
17
17
15
16
October
8.8
11
11
10
8
November
-1.4
-1
-1
2
0
December
-5.3
-2
-1
-6
-3
Average
4.6
-5.7
6.7
6.2
7.3
6.0
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
-20.7
-18
-19
-24
-13
-20
February
-21.8
-15
-25
-24
-15
-20
March
-12.3
-8
-8
-14
-13
-14
April
-5.5
-4
-2
-1
-4
May
0.6
1
1
2
2
June
6.9
7
7
9
7
July
12.5
17
12
11
13
August
12.0
12
13
13
13
September
7.1
8
9
8
7
October
2.2
4
4
2
2
November
-7.8
-7
-7
-3
-8
December
-13.8
-10
-9
-12
-10
Average
-5.9
-14.4
-2.0
-3.4
-1.1
-3.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
47.9
48
51
43
53
36
February
44.5
50
37
47
32
35
March
39.1
36
40
40
37
37
April
30.3
18
49
31
29
May
26.1
32
22
34
34
June
25.6
22
28
23
31
July
19.0
13
32
14
14
August
21.4
28
20
17
26
September
19.6
29
31
28
12
October
19.3
17
14
18
19
November
40.0
35
38
42
23
December
44.5
43
30
42
49
Average
31.1
43.7
28.6
32.2
28.9
27.6
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
8
8
8
10
February
9.9
8
10
10
10
12
March
10.0
9
9
12
10
11
April
9.2
9
9
6
11
May
9.4
10
9
10
9
June
8.6
9
9
8
9
July
7.9
7
9
7
7
August
7.6
7
7
9
7
September
10.0
9
9
10
12
October
10.0
10
10
8
12
November
9.6
11
8
8
10
December
9.9
11
9
10
9
Average
9.2
9.5
8.8
9.0
8.5
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
287°
265°
271°
275°
269°
February
241°
258°
272°
254°
270°
March
004°
017°
328°
280°
293°
April
352°
024°
021°
270°
May
346°
323°
321°
328°
June
046°
329°
255°
310°
July
190°
005°
246°
236°
August
339°
262°
276°
298°
September
352°
274°
323°
227°
October
328°
241°
354°
231°
November
282°
299°
280°
241°
December
296°
197°
276°
241°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.