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
80.2
87
62
77
86
77
February
90.1
80
86
89
89
94
March
90.2
90
90
84
91
91
April
94.9
94
94
100
95
May
90.8
81
89
94
91
June
94.3
91
93
97
96
July
94.3
87
98
91
93
August
91.1
79
91
89
97
September
93.2
81
97
95
99
October
91.6
91
99
91
94
November
82.8
75
75
83
90
December
82.1
97
76
79
84
Average
89.9
85.6
84.7
89.8
91.2
92.3
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
-12.3
-13
-9
-15
-8
-12
February
-11.3
-4
-10
-14
-15
-7
March
-2.0
-3
-4
-2
3
-4
April
6.2
8
5
8
3
May
16.1
21
14
15
14
June
21.3
25
20
24
20
July
24.1
23
24
26
24
August
22.7
23
25
22
23
September
16.8
21
20
18
15
October
7.3
8
12
10
3
November
-5.8
-1
-5
-1
-4
December
-10.4
-2
-16
-17
-7
Average
4.8
-7.0
8.6
6.5
7.0
5.6
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
-20.0
-19
-16
-24
-17
-19
February
-23.6
-16
-23
-27
-26
-19
March
-16.6
-17
-21
-15
-11
-17
April
-7.9
-5
-6
-5
-10
May
3.0
7
3
1
1
June
10.4
13
9
12
9
July
12.8
12
13
14
13
August
11.6
12
13
12
12
September
6.3
9
8
8
5
October
-1.4
1
2
1
-2
November
-11.0
-7
-11
-8
-13
December
-19.4
-12
-24
-25
-16
Average
-6.3
-18.6
-3.5
-5.8
-4.5
-5.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
41.1
48
37
57
45
39
February
29.4
33
36
32
34
22
March
22.5
18
23
31
19
31
April
13.4
13
14
8
20
May
11.3
6
12
10
11
June
16.7
7
24
14
16
July
10.1
8
9
10
13
August
9.5
12
9
11
9
September
10.9
6
7
9
11
October
20.1
23
2
11
39
November
47.6
48
47
31
41
December
32.9
12
44
56
22
Average
21.4
31.5
17.6
21.1
18.8
21.3
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
6.7
7
6
8
6
7
February
7.5
8
8
7
7
9
March
7.8
8
7
8
8
8
April
8.6
9
9
9
9
May
8.1
7
9
8
8
June
8.0
8
8
8
8
July
7.5
7
8
7
8
August
7.7
8
7
7
10
September
8.0
7
8
9
9
October
8.6
8
9
8
10
November
7.7
8
8
8
7
December
6.5
7
8
7
6
Average
7.8
7.5
7.5
8.2
7.8
8.2
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
291°
281°
320°
289°
289°
February
332°
287°
315°
304°
291°
March
013°
038°
319°
085°
329°
April
076°
045°
316°
310°
May
067°
025°
055°
049°
June
116°
027°
286°
053°
July
350°
279°
256°
276°
August
280°
261°
291°
244°
September
194°
249°
272°
285°
October
263°
263°
198°
279°
November
271°
332°
189°
273°
December
246°
327°
303°
267°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.