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
83.4
78
87
75
88
87
February
79.7
78
64
74
92
88
March
87.6
86
79
76
93
93
April
87.3
80
81
92
92
May
95.1
96
91
95
97
June
92.7
77
96
92
95
July
93.4
78
94
95
95
August
93.2
90
91
95
94
September
89.2
82
76
95
98
October
86.5
74
88
89
94
November
81.6
84
71
85
87
December
82.4
81
76
81
82
Average
88.3
80.7
80.9
82.8
91.5
92.6
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
-7.3
-3
-6
-9
-6
-4
February
-6.3
-2
-5
-8
-7
-6
March
0.0
2
-1
-1
3
1
April
7.4
8
7
13
6
May
17.3
19
20
18
16
June
22.8
24
22
24
24
July
24.8
21
25
24
26
August
23.0
22
23
25
22
September
18.8
21
19
18
17
October
10.9
12
12
15
7
November
1.3
1
4
2
5
December
-5.2
-1
-4
-4
-4
Average
7.9
-1.0
9.6
9.7
10.5
9.3
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
-18.9
-13
-15
-26
-13
-15
February
-17.0
-12
-18
-22
-19
-16
March
-11.3
-7
-12
-11
-8
-10
April
-3.1
-2
-2
0
-4
May
4.8
5
7
5
3
June
10.5
11
11
12
11
July
12.9
10
13
12
16
August
11.9
10
12
15
12
September
8.0
7
8
8
7
October
2.5
4
3
6
-1
November
-6.2
-6
-3
-4
-2
December
-13.0
-8
-11
-13
-12
Average
-3.5
-11.3
-1.0
-2.5
0.0
-1.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
31.5
43
30
43
24
31
February
34.7
37
54
48
18
24
March
26.8
37
36
48
21
19
April
21.7
37
29
13
16
May
11.4
14
14
8
10
June
8.6
9
13
10
9
July
8.4
11
18
7
9
August
9.2
17
16
3
12
September
11.6
18
20
11
10
October
19.3
33
24
8
18
November
32.0
41
43
23
25
December
32.5
28
45
33
37
Average
20.3
39.0
27.1
28.8
13.6
16.5
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
8.1
8
7
8
7
8
February
9.0
9
10
10
7
10
March
9.3
10
9
9
11
9
April
9.2
10
9
9
9
May
8.8
9
8
9
9
June
8.1
8
9
8
8
July
6.8
5
8
7
6
August
7.1
7
7
8
7
September
7.9
7
7
9
9
October
8.6
8
9
7
9
November
9.3
10
10
9
10
December
8.2
8
8
8
10
Average
8.4
9.0
8.2
8.5
8.3
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
251°
313°
261°
283°
295°
February
283°
229°
269°
232°
247°
March
286°
336°
290°
262°
296°
April
355°
308°
319°
290°
May
338°
184°
277°
309°
June
004°
250°
259°
246°
July
253°
254°
321°
255°
August
309°
260°
211°
282°
September
289°
306°
246°
228°
October
292°
202°
313°
240°
November
232°
260°
243°
210°
December
322°
280°
224°
298°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.