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
88.8
95
76
95
89
94
February
84.2
90
72
84
86
89
March
85.8
82
74
90
94
88
April
84.8
91
80
91
75
May
90.4
86
90
93
96
June
96.6
94
98
100
100
July
99.0
98
99
99
100
August
98.1
95
100
98
100
September
95.6
91
99
99
99
October
90.5
88
91
89
89
November
91.4
91
82
97
99
December
88.6
96
59
89
98
Average
91.1
88.4
87.6
90.0
94.1
93.7
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
2.8
2
1
5
4
5
February
1.5
8
2
4
-3
2
March
8.5
10
3
10
10
9
April
12.5
13
11
13
12
May
18.8
22
17
19
19
June
26.0
24
25
32
27
July
31.3
30
32
34
32
August
29.9
30
32
31
32
September
24.7
26
26
27
25
October
14.2
15
17
16
13
November
8.6
11
4
12
12
December
3.9
8
0
5
6
Average
14.2
6.3
15.2
15.8
16.7
16.0
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
-9.7
-12
-7
-8
-6
-7
February
-11.8
-4
-9
-10
-15
-8
March
-4.0
-4
-7
-5
-3
-3
April
-2.9
-1
-2
-1
-3
May
5.1
7
5
4
5
June
10.1
11
9
12
11
July
14.6
14
15
16
14
August
13.5
15
15
13
14
September
8.8
10
11
9
8
October
0.8
2
2
4
0
November
-4.2
-4
-7
-1
-3
December
-8.9
-5
-11
-8
-5
Average
0.5
-7.1
2.2
1.5
2.1
1.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
7.1
2
18
3
8
7
February
10.0
7
27
8
7
10
March
8.5
13
18
6
5
3
April
10.1
12
15
9
8
May
5.9
5
13
2
2
June
2.8
6
1
2
3
July
0.8
1
1
1
1
August
1.1
3
2
1
0
September
2.4
2
4
1
2
October
6.0
7
6
6
9
November
4.9
7
11
0
1
December
8.2
4
30
8
3
Average
5.7
8.0
8.9
7.6
3.9
3.8
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
10.0
7
9
13
12
10
February
11.2
11
11
14
10
12
March
10.5
9
11
12
11
11
April
11.4
11
15
11
11
May
10.0
9
11
11
12
June
8.6
7
8
9
11
July
8.0
7
8
8
8
August
8.1
8
7
9
9
September
9.0
8
9
9
9
October
10.2
9
9
11
11
November
10.6
9
12
12
10
December
11.2
10
12
14
10
Average
9.8
9.2
9.0
10.6
10.2
10.4
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
274°
269°
278°
247°
256°
February
249°
259°
285°
267°
256°
March
296°
264°
306°
257°
264°
April
306°
314°
321°
307°
May
279°
296°
272°
190°
June
173°
249°
300°
235°
July
313°
241°
104°
200°
August
273°
065°
272°
010°
September
219°
224°
261°
290°
October
333°
298°
270°
294°
November
267°
279°
255°
237°
December
278°
277°
227°
260°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.