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
66.2
0
55
90
74
74
February
74.7
0
87
94
87
92
March
77.0
0
89
91
92
71
April
79.3
0
94
92
96
89
May
90.9
96
92
96
87
June
92.5
87
96
94
96
July
95.2
94
94
95
96
August
89.3
69
93
97
98
September
73.5
0
90
83
October
75.5
0
93
100
93
November
73.5
0
90
100
94
December
68.0
0
77
0
91
Average
74.5
59.4
91.6
91.9
89.0
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
-2.2
-2
1
-4
-2
0
February
1.6
10
4
1
-7
0
March
7.8
11
7
9
9
9
April
14.4
16
16
12
16
13
May
21.1
24
23
20
19
June
26.8
28
28
28
27
July
27.2
28
28
27
28
August
26.0
27
27
28
27
September
23.6
25
23
21
October
15.5
17
17
14
14
November
7.2
10
10
5
12
December
2.6
6
3
2
2
Average
13.6
8.6
15.9
15.0
14.0
14.3
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
-9.6
-7
-4
-14
-8
-6
February
-8.5
-2
-5
-9
-14
-8
March
-2.6
1
-1
-1
0
0
April
3.3
6
4
3
4
2
May
9.9
10
12
9
9
June
15.3
14
16
17
15
July
15.9
16
18
17
18
August
14.9
16
17
16
15
September
12.5
14
12
11
October
5.3
7
4
14
3
November
-2.7
-1
0
0
2
December
-5.4
0
-4
2
-6
Average
3.8
-1.2
5.9
4.8
4.5
4.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
6.8
0
12
5
7
7
February
5.7
0
10
1
7
5
March
5.0
0
6
8
5
9
April
5.6
0
4
7
4
5
May
4.3
3
5
5
5
June
2.3
1
2
3
2
July
1.7
1
3
2
2
August
2.1
1
3
1
1
September
2.8
0
3
6
October
3.9
0
3
0
4
November
4.7
0
10
0
4
December
5.5
0
6
0
5
Average
3.8
2.8
4.6
4.1
4.3
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
8.1
8
8
10
7
7
February
8.8
9
9
11
7
9
March
9.8
11
9
10
10
9
April
10.3
11
11
12
10
10
May
8.3
7
10
9
9
June
7.2
6
8
7
7
July
5.6
5
6
6
6
August
5.6
6
6
7
5
September
6.6
6
6
8
October
8.5
9
8
10
9
November
9.1
9
10
11
11
December
7.9
8
9
0
7
Average
8.1
9.9
7.5
8.6
7.8
7.9
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
268°
274°
266°
330°
249°
February
247°
254°
259°
285°
296°
March
267°
230°
296°
187°
230°
April
257°
237°
225°
261°
290°
May
066°
167°
197°
032°
June
037°
247°
242°
194°
July
274°
251°
274°
227°
August
255°
231°
220°
241°
September
170°
287°
249°
October
271°
245°
285°
264°
November
248°
234°
258°
230°
December
244°
196°
360°
270°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.