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
85.4
91
71
85
64
97
February
89.5
91
92
92
84
85
March
95.7
93
96
97
89
99
April
98.8
99
98
100
100
May
98.1
96
96
99
99
97
June
98.2
95
97
99
100
July
97.9
92
99
97
99
August
97.5
100
94
98
97
September
93.2
96
100
95
93
October
91.8
92
91
90
95
November
91.8
94
87
87
90
December
86.6
88
78
86
93
Average
94.2
93.1
92.9
93.6
91.8
95.8
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
6.8
6.0
6.4
7.7
6.0
7.7
February
6.6
5.9
8.5
7.0
7.5
6.2
March
9.8
10.3
10.0
9.6
10.4
10.1
April
12.8
13.0
11.9
11.9
13.9
May
17.5
17.8
16.6
19.1
14.8
16.5
June
20.2
19.1
20.6
19.3
22.6
July
23.2
23.5
24.0
23.3
23.8
August
23.0
22.3
22.6
24.0
23.5
September
19.4
19.1
19.3
20.8
18.8
October
13.7
13.9
14.1
16.1
12.5
November
9.2
9.4
9.5
7.2
9.8
December
6.7
8.4
9.0
3.3
4.2
Average
13.7
10.0
14.2
14.6
14.1
14.1
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
2.1
0.1
1.6
3.6
2.1
3.5
February
1.2
0.4
3.5
2.2
1.8
1.1
March
3.6
5.2
3.9
2.7
4.9
3.2
April
5.9
6.2
5.4
4.7
5.7
May
9.8
9.5
9.0
10.6
8.5
9.4
June
12.4
11.9
12.3
12.3
13.8
July
14.6
15.0
14.5
15.1
15.0
August
14.9
14.5
14.9
16.1
15.1
September
12.4
12.5
11.9
12.4
12.0
October
7.6
8.1
8.0
9.0
8.0
November
4.2
5.5
4.0
1.1
5.5
December
2.3
3.9
5.0
-2.8
-2.9
Average
7.2
3.9
8.0
8.0
7.5
7.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
27.7
10
40
38
24
27
February
22.7
29
20
26
21
24
March
20.8
35
25
17
30
11
April
19.2
21
28
21
14
May
11.4
15
16
4
21
10
June
11.3
18
9
18
6
July
4.1
6
4
7
0
August
3.8
6
6
3
6
September
11.3
9
11
6
19
October
18.2
23
21
11
32
November
24.4
24
14
20
39
December
27.1
30
30
24
21
Average
16.4
22.0
19.1
16.3
16.7
16.0
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
7.5
6
8
7
6
8
February
7.6
7
8
8
7
8
March
8.1
9
9
7
9
9
April
9.0
9
9
9
9
May
7.9
8
9
8
8
8
June
8.2
8
9
9
8
July
8.1
8
9
7
8
August
7.9
8
9
8
7
September
7.9
8
8
9
8
October
7.7
8
8
7
9
November
7.9
9
7
7
10
December
7.4
8
7
7
9
Average
7.9
7.4
8.2
8.1
7.8
8.3
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
342°
084°
085°
100°
097°
February
105°
252°
108°
120°
154°
March
115°
126°
132°
040°
172°
April
245°
118°
182°
266°
May
187°
241°
223°
161°
231°
June
174°
217°
218°
182°
July
231°
163°
198°
164°
August
187°
269°
251°
188°
September
262°
262°
271°
128°
October
131°
013°
182°
115°
November
106°
150°
100°
116°
December
112°
088°
093°
122°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.