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
87.1
92
87
83
69
89
February
87.7
92
96
87
91
87
March
94.9
93
96
99
92
97
April
97.2
96
96
99
99
May
96.7
93
100
97
96
June
97.8
95
96
99
98
July
97.8
93
100
98
99
August
94.3
96
97
99
94
September
90.4
87
96
92
92
October
90.1
93
86
84
94
November
93.5
97
98
89
88
December
87.6
98
80
80
84
Average
93.3
92.5
93.9
93.5
92.0
93.6
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
6.5
6.7
5.4
7.2
5.7
7.7
February
6.6
5.7
9.5
6.5
8.1
5.5
March
11.4
11.9
11.8
11.5
11.8
11.5
April
14.5
14.9
13.1
13.0
16.5
May
19.7
18.1
22.5
15.4
18.5
June
22.1
21.0
22.6
21.6
26.0
July
26.0
26.6
26.8
26.5
26.8
August
26.3
25.0
27.1
28.5
25.8
September
22.4
22.1
22.3
25.1
21.6
October
15.6
15.3
16.3
20.0
13.9
November
9.7
9.4
10.0
7.7
10.0
December
6.3
8.9
9.0
1.6
3.2
Average
14.8
8.1
15.7
16.3
15.9
15.6
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
1.0
-1.1
0.5
2.7
-0.0
2.3
February
0.6
-1.4
3.2
1.3
1.6
0.1
March
3.1
4.4
3.6
2.6
4.2
2.5
April
5.5
5.7
4.7
4.2
5.7
May
9.2
8.4
10.5
7.7
8.0
June
11.7
11.1
11.1
12.0
13.3
July
13.5
14.3
13.3
14.0
13.6
August
13.7
14.0
14.1
14.8
14.0
September
11.6
11.8
10.9
12.0
11.5
October
7.1
8.1
7.7
7.9
7.5
November
3.6
4.7
3.0
0.1
4.9
December
1.1
3.1
3.9
-4.3
-2.3
Average
6.2
1.0
7.4
7.2
6.6
6.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2025
2024
2023
2022
2021
January
27.4
17
40
30
23
25
February
26.3
21
24
28
22
30
March
22.5
29
28
16
23
13
April
22.4
27
27
19
16
May
14.4
21
10
25
10
June
13.2
23
15
15
6
July
4.6
6
3
4
0
August
5.4
9
2
1
8
September
12.2
11
7
4
20
October
19.4
21
15
15
28
November
26.0
26
15
20
38
December
31.4
31
35
30
28
Average
18.4
22.8
21.4
16.1
15.7
17.0
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
6.1
4
7
5
5
6
February
7.6
7
7
8
7
9
March
6.8
7
6
7
7
7
April
6.9
7
6
8
7
May
6.0
7
6
7
6
June
6.1
6
6
6
6
July
5.9
6
6
5
6
August
5.4
5
6
5
6
September
5.2
5
6
6
5
October
5.8
6
5
5
7
November
6.6
6
5
7
7
December
5.7
6
5
5
8
Average
6.1
6.0
6.0
5.9
6.0
6.5
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
048°
058°
045°
066°
076°
February
060°
090°
145°
105°
139°
March
187°
121°
114°
186°
182°
April
193°
168°
169°
213°
May
206°
217°
201°
213°
June
207°
215°
211°
220°
July
219°
217°
219°
217°
August
222°
215°
217°
207°
September
227°
201°
225°
194°
October
181°
048°
189°
129°
November
123°
071°
054°
165°
December
115°
052°
048°
121°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.