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
92.9
95
95
89
97
94
February
90.8
73
88
93
100
96
March
90.8
89
96
79
92
99
April
92.7
90
80
100
98
May
95.4
96
98
88
99
98
June
90.0
92
88
95
84
87
July
88.1
72
84
89
90
August
92.3
96
80
93
95
September
93.0
83
97
98
93
October
91.4
71
92
96
95
November
93.3
96
99
98
77
December
91.6
75
97
96
81
Average
91.8
89.4
86.8
89.1
94.7
92.0
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
2025
2024
2023
2022
2021
January
18.6
18.6
17.6
16.6
19.8
19.1
February
18.1
18.1
16.3
17.1
21.1
18.5
March
18.2
17.0
17.3
16.1
20.3
17.6
April
19.8
18.1
18.1
21.3
19.3
May
19.8
20.3
18.6
18.5
20.5
19.1
June
21.6
21.6
21.6
19.8
22.6
21.1
July
23.6
23.0
23.1
23.3
22.6
August
24.6
24.5
24.1
25.0
23.5
September
24.8
23.8
23.3
27.8
23.1
October
23.9
22.0
23.3
23.1
22.6
November
21.6
20.6
22.6
20.5
21.8
December
18.9
18.0
20.0
16.5
16.1
Average
20.9
19.1
20.1
20.2
22.0
20.4
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
10.2
8.9
10.1
9.4
10.8
9.5
February
10.3
10.4
10.8
8.6
10.5
10.1
March
11.2
10.8
11.0
10.1
11.8
9.6
April
13.0
11.5
11.6
13.8
12.6
May
14.4
15.0
13.9
13.8
14.5
14.3
June
16.4
16.5
16.1
15.1
17.1
15.9
July
18.0
17.3
17.3
18.0
18.0
August
18.9
18.1
18.5
19.3
18.1
September
18.6
18.0
18.1
20.8
17.3
October
16.3
15.5
15.4
17.3
14.9
November
12.7
11.5
12.9
10.9
13.6
December
10.6
10.4
11.8
9.6
9.9
Average
14.0
12.3
13.7
13.6
14.7
13.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
5.4
1
5
14
1
2
February
7.2
11
17
11
1
0
March
6.9
10
6
17
2
2
April
1.1
2
1
0
0
May
1.1
0
0
3
0
1
June
0.8
1
1
2
1
0
July
0.1
0
0
0
1
August
0.7
0
4
1
1
September
0.4
1
2
1
0
October
0.4
0
0
1
2
November
1.5
0
1
3
0
December
4.2
1
5
6
14
Average
2.5
4.2
2.4
4.7
1.2
1.7
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
6.5
6
7
8
5
6
February
7.5
7
7
8
7
7
March
8.6
9
9
9
9
9
April
8.5
9
8
9
8
May
8.2
8
8
8
8
8
June
7.7
8
7
8
8
8
July
7.9
7
8
8
8
August
8.1
8
8
9
8
September
7.7
8
7
8
8
October
7.3
7
7
7
8
November
6.7
7
6
7
6
December
6.0
5
6
7
7
Average
7.6
7.7
7.4
7.6
7.7
7.6
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
255°
276°
229°
257°
241°
February
235°
231°
238°
253°
264°
March
246°
244°
246°
251°
254°
April
244°
253°
256°
251°
May
245°
254°
246°
251°
250°
June
245°
253°
247°
248°
248°
July
256°
250°
252°
254°
August
257°
253°
257°
254°
September
254°
243°
248°
255°
October
258°
246°
251°
256°
November
258°
249°
253°
258°
December
251°
261°
255°
245°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.