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
70.9
72
62
74
75
62
February
83.5
72
88
77
84
95
March
85.6
87
82
88
90
90
April
87.5
92
82
66
93
95
May
93.1
90
91
91
91
June
97.1
95
99
97
99
July
98.1
98
97
97
99
August
93.8
89
94
93
94
September
90.7
85
90
98
99
October
88.3
81
93
85
92
November
84.3
91
82
87
86
December
79.7
84
49
82
93
Average
87.9
81.4
86.0
85.0
90.1
91.9
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
-8.1
-7
-8
-9
-3
-8
February
-8.6
1
-6
-8
-11
-5
March
0.2
2
-5
0
8
2
April
8.4
12
4
4
12
8
May
19.2
23
17
19
17
June
25.5
27
25
28
26
July
27.1
26
27
29
27
August
25.8
26
26
28
26
September
20.6
23
22
23
20
October
10.6
11
14
14
8
November
1.4
4
0
5
5
December
-5.7
1
-9
-7
-1
Average
8.9
1.9
10.6
9.8
11.8
10.4
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
-17.6
-15
-17
-21
-11
-15
February
-18.7
-8
-17
-21
-20
-15
March
-10.7
-9
-15
-9
-5
-7
April
-3.8
1
-4
-4
-2
-3
May
6.7
9
7
5
5
June
13.8
16
13
14
14
July
15.9
14
15
18
17
August
14.6
15
16
16
15
September
9.7
12
10
11
9
October
1.7
2
3
5
0
November
-7.1
-5
-8
-4
-6
December
-13.0
-8
-16
-16
-11
Average
-2.8
-8.1
0.2
-1.3
0.7
0.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
24.1
27
26
32
25
21
February
19.1
19
13
25
14
12
March
14.3
19
26
13
2
12
April
14.2
14
23
30
11
13
May
7.7
7
13
4
10
June
5.0
5
5
4
2
July
2.1
3
3
1
1
August
4.2
7
3
4
3
September
6.2
9
5
3
3
October
11.1
14
5
14
7
November
19.7
5
37
17
7
December
21.9
9
54
25
12
Average
12.3
19.5
11.9
16.7
9.0
7.9
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
10.5
11
8
13
10
11
February
11.2
11
12
15
11
10
March
11.2
11
12
13
11
11
April
12.3
12
13
15
12
11
May
11.3
11
13
11
11
June
10.1
8
11
10
11
July
9.2
9
9
9
10
August
8.8
8
9
9
9
September
10.7
9
12
10
12
October
12.1
11
11
11
13
November
11.5
12
14
10
11
December
10.7
10
13
11
9
Average
10.8
11.3
10.0
12.2
10.5
10.8
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
281°
275°
294°
284°
242°
February
292°
283°
307°
265°
270°
March
335°
011°
302°
235°
268°
April
325°
002°
013°
346°
299°
May
102°
268°
244°
142°
June
077°
247°
289°
220°
July
274°
296°
154°
245°
August
311°
271°
224°
229°
September
111°
261°
252°
279°
October
328°
307°
311°
283°
November
280°
287°
268°
251°
December
293°
336°
275°
278°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.