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
86.2
80
79
88
96
92
February
84.7
76
79
77
87
94
March
86.6
78
86
80
97
87
April
90.9
90
95
97
96
May
91.4
79
91
95
97
June
95.2
87
93
98
99
July
91.9
87
91
86
99
August
88.4
85
93
96
99
September
90.5
85
98
98
93
October
91.3
85
94
89
89
November
87.0
92
81
92
91
December
90.7
96
88
85
90
Average
88.8
77.9
85.4
89.4
93.1
94.3
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
-4.7
-6
-1
-2
-1
-8
February
-4.9
1
-1
0
-7
2
March
3.5
3
1
5
8
1
April
9.5
12
8
12
8
May
17.8
22
15
16
16
June
20.9
23
19
24
20
July
23.1
23
25
25
22
August
22.3
23
25
23
23
September
17.3
19
22
18
19
October
10.5
12
15
11
7
November
1.4
6
-1
3
2
December
-4.6
2
-9
-10
1
Average
8.6
-1.6
11.7
10.8
10.3
9.2
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
-15.8
-16
-11
-13
-13
-19
February
-16.2
-12
-13
-12
-20
-11
March
-11.7
-11
-14
-7
-6
-13
April
-4.0
-3
-5
-4
-6
May
2.8
5
1
2
3
June
7.2
8
7
9
7
July
9.7
10
10
11
10
August
8.5
9
10
9
8
September
3.8
3
4
5
5
October
-3.5
-2
1
-3
-4
November
-9.2
-5
-12
-9
-9
December
-15.9
-10
-22
-22
-10
Average
-5.8
-13.2
-2.1
-3.5
-4.6
-4.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
15.0
22
11
21
15
6
February
23.0
26
31
39
20
10
March
21.0
44
27
22
8
24
April
13.6
16
17
7
21
May
9.2
8
9
12
16
June
11.9
20
19
4
7
July
10.2
11
13
2
12
August
8.6
13
9
11
3
September
8.9
9
4
6
5
October
11.0
21
6
4
29
November
17.7
6
34
9
12
December
12.9
2
30
22
12
Average
14.9
31.9
15.0
17.7
9.2
12.9
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
4.9
4
5
6
5
5
February
5.5
5
5
6
6
6
March
5.7
5
5
7
6
8
April
6.3
6
7
6
8
May
6.2
5
6
6
6
June
6.2
6
6
6
6
July
5.3
6
5
5
6
August
5.2
5
5
6
6
September
5.4
5
5
6
6
October
5.8
6
6
5
6
November
4.6
5
6
5
4
December
4.8
3
5
5
5
Average
5.5
4.8
5.2
5.9
5.5
6.0
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
305°
292°
286°
283°
288°
February
296°
334°
300°
280°
288°
March
357°
024°
304°
281°
314°
April
360°
332°
295°
292°
May
008°
293°
314°
336°
June
320°
320°
287°
293°
July
308°
332°
014°
289°
August
286°
289°
297°
299°
September
279°
287°
276°
299°
October
292°
279°
283°
294°
November
272°
302°
286°
275°
December
272°
288°
285°
267°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.