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
2024
2023
2022
2021
2020
January
86.3
78
93
87
88
91
February
85.8
93
93
89
67
78
March
87.4
80
94
84
87
86
April
91.9
91
90
94
92
May
85.0
88
75
95
89
June
90.9
86
93
93
87
July
95.0
93
93
98
95
August
94.0
92
96
96
94
September
90.0
82
91
97
95
October
87.7
95
69
93
87
November
93.4
95
93
99
91
December
89.9
91
85
94
96
Average
89.2
83.4
90.7
87.0
92.1
90.1
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
2024
2023
2022
2021
2020
January
8.4
8
12
6
8
10
February
11.3
10
13
11
7
12
March
13.9
14
14
15
16
16
April
19.8
23
18
20
17
May
23.6
22
24
25
21
June
28.5
28
29
30
29
July
31.5
32
32
32
33
August
29.7
29
31
29
30
September
26.3
26
27
27
26
October
21.7
22
19
23
21
November
15.1
14
17
14
18
December
10.9
13
11
13
11
Average
19.1
10.9
21.3
20.3
20.2
20.3
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
2020
January
-1.8
0
3
-4
0
2
February
1.5
0
3
0
0
2
March
3.7
5
4
4
5
6
April
8.9
11
8
9
7
May
13.1
12
14
13
12
June
18.1
17
18
20
19
July
21.9
23
22
21
23
August
20.7
20
21
21
22
September
17.1
17
17
17
17
October
11.6
10
10
14
13
November
4.2
2
6
3
7
December
1.5
2
2
3
1
Average
9.3
1.7
11.0
10.0
10.4
11.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.1
14
9
15
7
10
February
11.9
6
11
10
25
16
March
12.1
17
12
14
7
13
April
8.4
13
7
5
13
May
9.1
9
12
8
9
June
4.6
7
3
4
2
July
4.5
3
8
4
4
August
6.0
5
12
5
8
September
8.3
14
11
5
5
October
9.2
5
19
7
9
November
6.9
5
9
4
5
December
8.7
7
19
3
5
Average
8.6
12.5
8.3
11.1
6.6
8.0
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
2024
2023
2022
2021
2020
January
7.3
8
7
7
6
8
February
7.7
7
8
8
8
7
March
8.6
8
8
8
9
8
April
8.4
9
9
8
9
May
7.8
7
9
7
9
June
7.1
7
6
7
7
July
6.2
6
6
6
6
August
6.1
6
6
5
6
September
6.8
7
7
7
7
October
6.9
6
7
7
6
November
6.8
6
7
7
7
December
6.8
7
8
7
7
Average
7.3
7.7
7.0
7.3
6.9
7.2
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
2020
January
283°
271°
323°
313°
286°
February
290°
259°
242°
344°
266°
March
310°
289°
237°
254°
195°
April
200°
270°
282°
271°
May
063°
075°
235°
070°
June
138°
188°
204°
173°
July
202°
213°
229°
192°
August
184°
192°
130°
176°
September
045°
028°
200°
067°
October
257°
011°
165°
274°
November
323°
234°
298°
234°
December
273°
273°
249°
256°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.