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
72.2
55
59
86
75
75
February
86.1
92
85
91
84
92
March
89.1
92
89
86
95
77
April
92.8
92
93
95
93
May
91.0
96
90
94
93
June
93.0
88
96
96
99
July
90.7
92
88
94
96
August
93.0
86
93
97
100
September
92.1
87
95
100
83
October
91.5
91
93
92
95
November
90.6
94
88
100
93
December
77.8
69
71
82
96
Average
87.9
79.8
86.0
90.0
92.6
91.3
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
-1.9
-1
2
-3
0
2
February
3.3
11
5
2
-4
2
March
9.4
13
8
10
12
10
April
15.3
18
13
17
16
May
22.1
25
23
21
21
June
28.2
29
29
30
29
July
28.9
29
29
28
30
August
27.9
28
28
30
29
September
25.4
26
24
28
23
October
17.0
18
16
20
16
November
8.8
11
11
10
13
December
4.0
7
4
7
4
Average
14.8
7.4
17.0
15.8
16.5
16.2
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
-9.9
-8
-5
-13
-7
-5
February
-7.0
-3
-5
-9
-14
-6
March
-1.4
1
-1
-1
1
1
April
3.5
3
3
6
4
May
9.4
11
11
11
10
June
15.3
15
16
18
17
July
17.6
17
17
18
19
August
15.4
15
17
18
16
September
12.1
14
12
13
12
October
6.0
8
3
10
4
November
-1.0
-1
0
-1
2
December
-4.1
-1
-3
-3
-5
Average
3.9
-4.8
5.7
4.8
5.9
5.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
18.5
27
31
12
18
13
February
11.4
4
17
11
16
10
March
11.5
12
16
21
8
15
April
11.2
9
17
9
11
May
7.8
5
13
10
8
June
4.4
4
4
6
3
July
2.6
3
5
5
2
August
2.3
2
4
1
1
September
5.8
6
5
2
11
October
10.4
16
7
12
8
November
9.2
6
23
4
7
December
12.1
21
19
6
7
Average
9.1
14.2
10.5
10.8
7.7
7.6
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
8.1
8
8
9
8
7
February
8.5
8
10
10
8
8
March
9.9
11
10
10
9
9
April
9.8
11
12
9
9
May
7.7
8
8
8
9
June
6.5
6
7
6
7
July
5.6
5
6
6
5
August
5.4
6
6
5
6
September
6.2
5
6
7
8
October
7.8
9
7
8
8
November
8.1
8
9
10
9
December
7.9
8
10
10
8
Average
7.7
9.3
7.6
8.1
7.6
7.6
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
287°
297°
296°
344°
279°
February
269°
272°
290°
309°
320°
March
297°
338°
299°
066°
318°
April
265°
250°
280°
301°
May
051°
108°
041°
012°
June
017°
275°
272°
173°
July
283°
283°
331°
296°
August
343°
309°
215°
299°
September
014°
319°
281°
305°
October
298°
282°
356°
295°
November
271°
253°
268°
247°
December
293°
190°
266°
275°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.