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
82.3
71
87
87
83
81
February
84.1
93
89
85
80
87
March
89.9
94
86
90
89
87
April
92.2
99
96
94
90
May
92.9
92
87
96
92
June
98.2
97
99
97
100
July
97.0
99
97
97
96
August
95.8
96
98
98
96
September
95.2
97
94
99
89
October
88.3
89
93
89
80
November
92.7
94
95
100
92
December
88.6
84
77
96
93
Average
91.1
86.4
92.6
92.2
93.3
90.5
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
8.1
5
11
8
7
9
February
11.0
17
13
10
3
10
March
16.3
19
14
16
18
18
April
20.3
21
21
20
20
May
24.8
26
25
22
22
June
30.6
31
31
30
31
July
33.0
34
36
31
33
August
31.4
33
34
32
31
September
29.0
30
30
31
27
October
21.5
21
24
22
21
November
15.1
17
14
16
18
December
11.3
12
10
17
10
Average
20.1
13.3
21.9
22.0
20.8
20.8
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
-3.7
-5
0
-5
-1
0
February
-1.6
4
1
-3
-6
0
March
5.1
7
4
4
6
7
April
8.5
8
9
9
8
May
14.6
14
16
13
13
June
19.5
19
20
20
20
July
21.5
22
21
21
22
August
20.7
22
21
22
19
September
17.3
17
17
18
16
October
9.9
11
9
12
8
November
3.8
5
4
5
6
December
1.2
3
2
5
-1
Average
9.0
1.9
10.4
9.8
10.4
9.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
8.5
15
6
7
13
7
February
10.2
8
7
12
20
9
March
6.8
4
9
12
9
7
April
6.0
4
6
6
6
May
6.7
7
12
9
9
June
2.5
3
2
3
1
July
3.0
2
5
2
4
August
3.5
3
1
3
3
September
2.4
1
3
0
3
October
8.9
9
8
8
13
November
4.3
4
4
2
5
December
4.0
7
3
3
5
Average
5.8
8.4
4.8
6.1
6.1
5.7
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
2024
2023
2022
2021
2020
January
9.3
8
9
10
9
9
February
10.0
11
9
11
10
9
March
10.7
12
11
11
11
10
April
10.8
11
12
11
9
May
8.4
7
10
8
8
June
8.0
6
8
7
9
July
7.2
9
8
6
7
August
7.0
7
8
7
7
September
7.5
7
8
8
7
October
9.3
9
10
9
10
November
9.4
9
10
10
11
December
9.3
10
9
11
9
Average
9.0
10.0
8.6
9.5
8.8
8.7
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
268°
246°
272°
265°
223°
February
210°
210°
254°
003°
255°
March
200°
212°
231°
194°
195°
April
215°
199°
224°
234°
May
180°
178°
156°
143°
June
194°
184°
192°
197°
July
222°
205°
211°
199°
August
243°
177°
185°
209°
September
180°
174°
193°
204°
October
225°
230°
218°
237°
November
201°
220°
214°
202°
December
228°
215°
206°
233°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.