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
79.0
76
86
76
92
82
February
73.2
86
56
65
79
87
March
91.1
92
93
89
85
86
April
94.0
84
99
99
85
May
97.9
94
100
100
98
June
97.2
93
95
100
98
July
93.7
88
93
99
97
August
92.9
94
87
96
95
September
92.9
94
96
89
95
October
91.8
87
94
95
88
November
77.3
67
91
78
78
December
75.1
62
62
78
76
Average
89.4
85.6
85.0
89.8
90.9
90.4
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
-6.4
-7
-2
-5
-3
-13
February
-4.9
-2
-3
0
-6
-3
March
0.9
2
1
4
-2
-1
April
8.0
5
8
8
8
May
14.4
13
17
13
17
June
18.3
17
22
13
19
July
20.1
19
21
14
22
August
19.1
20
17
18
20
September
14.3
13
14
13
14
October
7.2
6
7
7
7
November
-2.5
0
-1
-7
-3
December
-4.5
-5
-6
-6
-2
Average
6.2
-3.4
7.0
8.7
5.1
7.0
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
-13.4
-15
-8
-11
-9
-20
February
-11.5
-10
-9
-6
-13
-11
March
-8.1
-6
-8
-4
-13
-10
April
-2.9
-3
-1
-3
-1
May
5.5
5
6
6
6
June
10.2
9
12
10
9
July
12.6
13
13
12
12
August
11.3
12
11
10
12
September
6.9
6
8
5
7
October
0.5
-1
0
0
0
November
-8.6
-5
-7
-12
-10
December
-10.2
-12
-14
-13
-9
Average
-2.6
-11.7
0.1
1.0
-2.4
-2.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
10.0
7
7
16
7
6
February
17.7
7
40
26
9
13
March
7.7
9
8
10
15
9
April
7.0
14
1
6
10
May
6.1
9
1
3
4
June
8.7
20
2
15
9
July
13.4
17
20
9
12
August
16.9
18
28
14
16
September
14.0
13
23
8
19
October
12.5
14
11
14
12
November
16.0
32
15
19
12
December
16.2
24
25
8
18
Average
11.2
7.8
17.1
13.5
10.1
11.3
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
3.2
3
3
5
3
2
February
3.5
5
3
4
4
4
March
3.7
3
4
4
3
4
April
4.2
4
4
5
4
May
4.4
4
5
4
4
June
4.2
4
5
3
4
July
4.0
4
5
2
4
August
3.9
4
4
4
4
September
3.8
4
4
4
4
October
3.8
3
5
3
3
November
3.2
3
3
3
3
December
3.2
3
3
3
3
Average
3.8
3.6
3.7
4.2
3.5
3.8
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
043°
031°
358°
020°
045°
February
345°
357°
336°
008°
360°
March
339°
343°
351°
356°
352°
April
329°
307°
331°
317°
May
274°
292°
286°
298°
June
298°
289°
340°
276°
July
303°
277°
304°
297°
August
293°
278°
258°
311°
September
273°
296°
342°
310°
October
011°
356°
341°
010°
November
135°
013°
020°
007°
December
018°
027°
359°
003°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.