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
70.9
54
60
67
86
87
February
81.3
94
82
78
83
73
March
82.5
77
73
76
95
88
April
88.8
93
89
91
88
May
90.0
95
86
95
90
June
92.7
79
97
99
97
July
95.7
91
95
91
98
August
97.6
93
99
97
99
September
95.1
97
85
95
97
October
91.6
96
96
90
92
November
90.4
90
76
95
94
December
83.2
84
79
90
87
Average
87.3
73.9
85.9
85.9
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
2.3
2
4
-1
2
5
February
4.6
6
7
4
0
3
March
7.9
11
6
10
12
10
April
13.2
15
13
15
11
May
19.7
19
21
19
19
June
24.6
23
25
27
26
July
27.2
26
27
26
29
August
26.4
24
26
28
27
September
23.5
22
22
24
24
October
17.6
17
16
20
16
November
9.6
10
11
10
13
December
5.4
8
4
8
5
Average
14.1
6.3
15.1
15.1
15.9
15.6
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
-4.2
-3
-1
-7
-2
-1
February
-4.9
-1
-3
-5
-5
-2
March
-1.5
2
-1
0
1
2
April
4.5
5
4
6
3
May
10.5
9
12
11
10
June
16.3
14
16
19
17
July
19.2
19
19
19
21
August
18.5
17
19
20
19
September
15.4
15
15
15
15
October
9.9
10
7
13
9
November
2.8
3
4
3
6
December
-1.8
3
-1
2
-1
Average
6.4
-1.0
7.5
7.1
8.5
8.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
27.7
42
35
34
14
15
February
17.8
8
14
31
18
15
March
17.6
20
31
23
6
12
April
12.0
13
15
10
12
May
9.6
10
9
10
11
June
6.4
8
5
6
3
July
4.7
5
3
11
3
August
4.7
6
5
5
7
September
7.2
6
16
5
8
October
14.4
15
18
15
15
November
16.3
17
28
17
14
December
18.8
20
18
12
18
Average
13.6
23.8
14.5
16.1
10.1
10.1
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
9.6
10
8
11
8
10
February
10.2
10
11
12
9
10
March
10.0
10
10
10
11
10
April
9.4
9
9
8
10
May
8.5
8
9
8
9
June
8.1
7
8
8
8
July
7.3
7
8
8
7
August
7.5
8
7
6
8
September
8.0
7
8
8
9
October
8.8
8
10
8
9
November
10.0
10
10
10
10
December
9.3
8
10
10
11
Average
8.9
10.0
8.3
9.1
8.4
9.0
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
225°
236°
252°
264°
226°
February
237°
235°
228°
251°
255°
March
246°
261°
251°
247°
236°
April
252°
252°
266°
274°
May
003°
179°
293°
236°
June
300°
252°
224°
266°
July
258°
255°
263°
266°
August
276°
245°
249°
255°
September
004°
244°
215°
201°
October
246°
199°
205°
223°
November
225°
219°
225°
228°
December
218°
200°
212°
221°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.