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
86.7
86
81
83
93
87
February
84.1
84
97
87
87
82
March
91.9
95
89
92
93
91
April
93.8
95
92
95
93
May
97.6
98
95
97
100
96
June
98.5
98
99
100
99
July
97.7
93
97
100
99
August
98.7
99
100
99
100
September
97.2
98
98
100
96
October
95.6
98
94
98
98
November
91.7
93
88
88
97
December
89.7
81
93
86
92
Average
93.7
91.3
93.4
93.6
95.4
94.3
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
2025
2024
2023
2022
2021
January
18.3
15.8
16.6
21.0
19.1
18.8
February
20.7
20.8
22.3
21.8
17.6
17.1
March
24.5
26.1
24.3
25.1
23.3
24.5
April
26.5
27.3
26.0
27.6
25.8
May
30.5
30.5
32.2
30.3
31.8
29.1
June
33.2
33.6
34.7
35.0
33.2
July
34.2
33.0
35.8
35.6
33.3
August
34.8
35.2
38.2
33.7
34.3
September
32.5
32.6
35.0
33.0
32.1
October
28.6
31.0
27.8
28.1
29.6
November
23.0
26.1
21.5
21.1
23.3
December
20.6
21.6
20.0
22.0
25.3
Average
26.9
23.3
28.0
28.1
27.5
27.3
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
8.9
6.2
7.2
12.0
8.3
9.5
February
11.3
11.1
12.6
12.5
6.4
8.0
March
15.2
15.8
15.8
16.6
11.5
14.4
April
17.4
19.3
16.3
18.8
17.3
May
22.0
22.3
23.3
22.1
23.0
22.0
June
24.9
26.1
25.1
25.3
25.6
July
25.4
22.3
26.3
26.1
25.8
August
25.9
26.6
27.3
25.6
24.6
September
24.0
24.0
25.3
23.3
23.5
October
19.0
20.1
18.5
17.6
20.5
November
13.9
16.8
13.4
13.0
13.4
December
11.4
12.3
11.0
14.9
16.6
Average
17.9
13.9
18.8
18.9
18.0
18.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
7.4
10
11
6
8
5
February
6.0
5
4
5
6
5
March
4.6
3
5
6
7
6
April
4.5
2
7
4
9
May
4.0
3
6
4
2
12
June
4.1
8
1
2
5
July
5.3
15
3
2
8
August
4.3
3
0
9
1
September
6.3
5
3
1
7
October
5.3
1
13
3
4
November
7.3
7
11
16
5
December
5.9
7
3
5
1
Average
5.3
5.0
6.3
4.9
5.3
5.8
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
2025
2024
2023
2022
2021
January
9.6
10
10
10
10
10
February
9.8
10
11
10
10
10
March
10.2
11
9
12
10
11
April
10.5
11
10
12
10
May
9.5
10
10
8
10
10
June
8.3
9
9
8
8
July
7.2
7
7
8
6
August
7.2
6
8
8
7
September
7.5
8
7
7
7
October
8.4
9
9
8
8
November
8.5
9
8
10
8
December
8.8
9
8
9
10
Average
8.9
10.1
9.0
8.9
9.1
8.7
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
039°
011°
208°
339°
326°
February
108°
209°
192°
001°
073°
March
186°
130°
137°
164°
122°
April
154°
117°
149°
112°
May
148°
134°
135°
166°
133°
June
133°
193°
164°
154°
July
174°
191°
186°
168°
August
114°
170°
163°
161°
September
057°
130°
072°
082°
October
095°
095°
110°
121°
November
100°
054°
082°
089°
December
105°
069°
137°
176°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.