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
77.3
68
63
81
86
91
February
86.7
75
74
90
86
95
March
84.3
74
79
81
90
89
April
90.6
96
75
83
96
May
85.1
91
68
78
85
June
90.3
90
92
99
72
July
92.6
90
94
82
93
August
91.6
85
97
86
87
September
89.2
87
94
96
80
October
78.4
75
84
81
86
November
77.7
73
64
81
85
December
77.8
78
67
84
88
Average
85.2
72.4
82.2
82.9
86.1
88.2
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
-15.5
-12
-12
-20
-11
-14
February
-13.0
-8
-13
-17
-16
-10
March
-4.6
-5
-6
-4
-1
-4
April
4.0
5
4
5
2
May
14.2
19
13
13
13
June
20.8
24
19
19
18
July
23.3
21
23
24
24
August
21.5
22
22
20
22
September
15.8
20
18
18
12
October
6.7
8
8
11
4
November
-6.9
-3
-3
-1
-6
December
-12.3
-4
-10
-15
-13
Average
2.9
-9.6
6.9
5.0
4.9
3.0
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
-22.2
-19
-19
-29
-17
-19
February
-24.1
-18
-26
-29
-24
-22
March
-16.8
-16
-20
-17
-9
-16
April
-7.8
-6
-6
0
-8
May
3.5
6
3
8
4
June
12.3
14
9
16
12
July
15.9
12
14
21
20
August
13.6
14
13
13
17
September
9.1
12
9
11
8
October
1.7
3
1
5
1
November
-11.7
-8
-10
-7
-9
December
-19.4
-11
-19
-23
-17
Average
-6.7
-18.1
-3.5
-5.6
-2.6
-4.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
46.4
45
44
39
50
56
February
36.0
39
38
21
38
30
March
26.2
39
25
25
23
28
April
15.1
10
25
20
13
May
16.1
8
30
22
32
June
15.0
8
25
9
24
July
12.6
22
11
3
18
August
10.3
12
9
18
12
September
13.3
7
11
8
21
October
27.5
15
38
14
38
November
51.7
45
49
25
53
December
41.0
34
44
38
16
Average
26.3
40.7
21.0
26.2
21.1
27.0
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
6.6
7
6
7
7
6
February
7.1
6
7
8
8
7
March
8.0
9
6
8
10
8
April
7.9
8
9
9
8
May
7.9
7
9
10
8
June
7.7
7
9
10
8
July
7.5
8
7
8
8
August
7.4
7
8
8
8
September
8.2
7
9
9
9
October
8.6
7
10
8
9
November
9.1
10
9
10
8
December
7.0
7
8
7
5
Average
7.7
7.5
7.2
8.3
8.3
7.8
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
296°
241°
281°
203°
270°
February
335°
269°
290°
283°
261°
March
341°
289°
306°
069°
205°
April
045°
035°
297°
330°
May
080°
061°
309°
019°
June
112°
337°
169°
057°
July
312°
307°
315°
282°
August
299°
262°
318°
339°
September
194°
283°
250°
291°
October
341°
317°
349°
270°
November
295°
325°
285°
282°
December
264°
034°
222°
263°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.