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
77.7
84
66
74
81
83
February
77.2
79
76
68
81
75
March
82.6
79
84
66
94
82
April
83.3
83
83
94
93
May
93.5
98
89
95
98
June
91.1
84
90
92
96
July
92.6
85
97
95
90
August
94.0
85
92
96
95
September
89.7
91
86
96
91
October
85.8
81
91
91
83
November
81.7
81
82
84
87
December
78.8
73
80
79
83
Average
85.9
80.2
83.2
84.0
90.8
88.9
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
-6.2
-5
-3
-10
-5
-4
February
-4.1
-1
-5
-6
-4
-3
March
1.0
3
2
0
3
2
April
7.9
9
8
12
7
May
17.9
19
19
18
18
June
22.5
22
22
24
25
July
25.6
25
25
24
27
August
24.0
22
24
27
23
September
19.6
22
19
20
19
October
12.7
15
14
14
11
November
2.8
3
5
4
6
December
-3.2
-1
1
-3
-1
Average
8.8
-1.1
10.8
10.5
11.1
10.6
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
-14.6
-12
-10
-21
-10
-11
February
-14.5
-10
-15
-15
-14
-14
March
-8.8
-4
-6
-7
-8
-7
April
-1.7
0
1
1
-2
May
6.0
6
7
7
6
June
11.8
12
12
13
11
July
15.3
17
15
14
17
August
14.3
13
15
16
14
September
10.0
12
10
10
8
October
4.5
7
3
6
3
November
-4.1
-4
-3
-3
-2
December
-10.2
-7
-5
-11
-8
Average
-1.9
-9.1
2.3
1.3
2.0
1.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
42.4
40
50
38
41
35
February
33.8
29
38
44
27
34
March
25.2
27
23
43
14
21
April
23.5
22
21
16
22
May
13.0
10
17
12
6
June
14.3
24
18
13
5
July
8.6
18
9
5
9
August
11.1
23
16
4
10
September
11.6
12
8
10
13
October
18.2
26
12
9
22
November
26.6
25
31
24
14
December
35.8
44
35
40
29
Average
21.6
31.2
24.6
22.8
16.0
16.8
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
9.2
10
9
8
8
8
February
9.2
7
9
9
9
9
March
9.6
10
9
10
10
10
April
9.9
10
9
10
11
May
8.4
10
8
8
9
June
8.1
9
8
8
9
July
7.2
6
8
8
7
August
6.7
7
6
7
8
September
6.6
7
7
6
6
October
7.9
6
7
9
7
November
8.3
7
8
8
8
December
8.5
8
10
9
7
Average
8.4
9.0
7.9
8.1
8.1
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
245°
053°
258°
247°
262°
February
261°
024°
344°
243°
245°
March
051°
255°
294°
259°
051°
April
064°
023°
062°
036°
May
289°
063°
262°
264°
June
078°
214°
244°
213°
July
214°
242°
242°
159°
August
226°
229°
243°
239°
September
217°
275°
253°
249°
October
216°
236°
077°
283°
November
263°
255°
249°
275°
December
047°
058°
287°
274°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.