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
2025
2024
2023
2022
2021
January
83.7
90
76
78
91
94
February
83.4
96
84
81
78
March
92.3
93
88
92
90
April
93.4
95
93
92
97
May
95.2
92
95
95
97
June
95.6
96
97
97
92
July
96.3
95
93
97
97
August
96.3
100
98
94
98
September
95.1
93
97
98
97
October
92.7
99
89
95
95
November
90.0
87
93
88
96
December
83.4
78
94
64
83
Average
91.7
90.1
92.0
91.6
91.5
93.1
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
2025
2024
2023
2022
2021
January
11.0
8.5
9.0
14.8
12.6
11.1
February
14.3
18.8
16.6
13.9
7.0
March
19.1
20.3
18.6
19.6
19.8
April
22.6
24.3
23.1
23.3
21.3
May
27.7
28.8
28.6
28.8
25.5
June
31.4
33.0
32.8
32.2
30.8
July
33.0
32.3
33.6
35.6
32.3
August
32.6
34.6
35.0
32.5
32.8
September
30.4
29.8
32.3
31.6
30.8
October
24.4
27.6
25.3
25.8
25.1
November
17.3
19.6
18.1
16.8
17.0
December
13.7
13.0
15.1
13.3
18.3
Average
21.6
8.4
24.3
24.6
24.2
22.8
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2025
2024
2023
2022
2021
January
1.1
-2.3
-1.3
5.2
-1.9
2.0
February
3.8
7.4
6.2
1.3
-2.3
March
8.1
10.1
8.5
6.7
8.1
April
11.3
13.9
11.9
12.0
10.0
May
16.9
18.3
17.8
18.1
15.5
June
21.1
21.6
21.6
22.1
21.3
July
23.1
23.0
24.0
24.8
21.8
August
22.5
23.1
24.5
22.8
22.1
September
19.5
20.3
20.1
18.8
18.8
October
12.8
13.4
14.5
12.0
14.9
November
6.0
9.4
7.5
6.2
4.7
December
4.0
4.7
4.4
5.9
8.0
Average
11.0
-2.3
13.7
13.9
12.8
12.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
10.0
8
19
11
10
8
February
13.5
9
16
15
13
March
7.1
4
10
10
4
April
5.9
4
4
8
6
May
5.5
8
3
3
5
June
3.5
2
2
4
6
July
2.9
3
3
2
3
August
3.8
0
2
5
3
September
4.8
9
3
2
2
October
6.9
2
11
5
4
November
7.0
7
6
8
3
December
10.2
14
3
20
8
Average
6.7
7.9
6.4
5.8
6.7
5.1
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
2025
2024
2023
2022
2021
January
7.6
7
7
8
8
8
February
8.2
8
8
9
8
March
8.6
8
9
9
8
April
8.5
9
8
9
8
May
7.4
7
7
8
8
June
6.7
6
6
6
6
July
6.3
6
6
7
6
August
6.0
6
7
6
6
September
6.1
7
6
6
6
October
6.9
6
7
7
7
November
6.8
7
7
6
7
December
7.3
7
7
7
8
Average
7.1
6.8
6.9
7.0
7.3
7.2
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2025
2024
2023
2022
2021
January
324°
001°
283°
334°
298°
February
269°
260°
299°
035°
March
198°
138°
225°
130°
April
230°
111°
185°
227°
May
206°
128°
196°
140°
June
196°
119°
161°
167°
July
227°
238°
192°
195°
August
092°
147°
135°
147°
September
053°
108°
050°
102°
October
115°
297°
260°
237°
November
103°
356°
047°
218°
December
053°
289°
061°
210°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.