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
75.0
85
61
60
88
79
February
80.8
82
84
75
85
85
March
79.5
67
80
73
86
85
April
80.2
80
83
88
85
May
89.9
94
89
92
91
June
85.9
70
87
92
91
July
88.6
79
93
89
84
August
86.3
79
79
88
91
September
87.1
80
85
85
92
October
83.0
81
89
77
84
November
83.4
78
84
91
91
December
76.6
60
65
80
80
Average
83.1
76.5
77.6
81.4
87.0
87.1
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
-4.8
-3
-1
-6
-3
-2
February
-2.3
0
-3
-2
-3
-2
March
2.5
4
3
3
5
3
April
9.6
11
10
13
8
May
17.7
18
20
18
18
June
22.4
21
22
25
24
July
25.9
27
27
23
26
August
24.6
22
25
26
26
September
20.5
22
20
20
21
October
14.0
15
17
15
12
November
4.9
4
7
6
8
December
-1.3
2
3
0
1
Average
10.1
0.3
11.8
12.3
12.1
11.9
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
-13.2
-12
-8
-18
-9
-12
February
-14.9
-11
-15
-13
-13
-13
March
-8.9
-4
-5
-6
-7
-7
April
-1.7
1
0
0
-2
May
4.6
4
6
4
5
June
10.3
11
10
13
10
July
14.1
17
13
12
15
August
13.0
13
15
16
12
September
8.7
10
9
10
8
October
3.7
6
4
5
2
November
-4.5
-5
-1
-3
-1
December
-9.0
-6
-4
-9
-6
Average
-1.6
-9.1
2.0
1.4
1.7
0.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
21.6
17
40
30
11
15
February
15.0
14
12
25
10
13
March
17.6
32
23
22
12
9
April
15.0
9
24
15
12
May
10.9
14
8
10
11
June
11.1
21
12
12
3
July
6.5
10
7
10
4
August
8.3
16
15
4
6
September
9.7
14
10
14
5
October
10.8
14
5
9
10
November
15.8
24
14
10
10
December
19.0
26
40
18
11
Average
13.6
21.9
17.8
16.3
10.9
8.6
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
7.2
7
7
7
7
7
February
7.6
8
7
8
7
7
March
8.1
8
7
8
9
8
April
7.8
7
8
9
9
May
7.3
8
7
7
8
June
6.2
5
6
7
6
July
5.4
4
6
6
5
August
5.2
5
5
5
6
September
5.8
5
5
6
7
October
6.1
5
5
5
7
November
6.9
7
7
7
7
December
7.2
7
9
7
7
Average
6.8
7.6
6.1
6.7
6.7
7.1
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
295°
346°
323°
338°
330°
February
289°
317°
295°
314°
273°
March
318°
342°
284°
272°
328°
April
255°
335°
355°
309°
May
317°
281°
313°
290°
June
042°
258°
239°
227°
July
201°
243°
286°
219°
August
254°
286°
228°
259°
September
349°
300°
255°
237°
October
261°
208°
338°
257°
November
274°
267°
286°
252°
December
314°
355°
298°
281°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.