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
87.4
80
92
85
95
90
February
86.5
95
93
82
78
86
March
88.3
85
93
84
88
88
April
86.3
79
94
92
89
May
86.8
96
83
93
88
June
91.8
88
96
95
95
July
96.0
96
99
94
96
August
97.2
96
99
96
98
September
93.3
84
98
98
97
October
87.9
87
88
97
77
November
95.5
99
94
100
93
December
86.9
80
85
88
94
Average
90.1
86.5
90.2
91.2
92.9
91.0
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
5.3
5
8
3
5
7
February
7.0
7
8
7
4
8
March
9.9
12
10
10
12
12
April
14.9
17
14
16
13
May
20.2
20
21
21
19
June
25.3
24
26
26
26
July
29.0
29
30
28
30
August
28.0
27
30
28
28
September
24.7
24
25
25
24
October
19.1
19
18
21
18
November
12.2
12
14
12
15
December
7.5
9
8
10
7
Average
15.8
7.8
17.3
17.5
17.2
17.3
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
-1.0
0
3
-4
-1
1
February
-1.8
0
0
-2
-2
1
March
2.4
5
2
3
3
4
April
7.1
9
7
7
6
May
11.9
11
13
11
10
June
17.4
16
18
18
18
July
21.7
22
22
21
23
August
21.1
20
22
22
21
September
17.6
17
17
18
17
October
12.1
12
11
14
11
November
4.8
4
7
5
7
December
1.6
3
2
4
1
Average
8.7
1.7
10.0
9.9
9.9
9.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
13.4
22
14
17
3
8
February
14.2
8
9
18
28
17
March
12.5
18
12
10
7
14
April
11.2
11
6
11
13
May
11.3
5
14
11
6
June
5.2
3
5
4
4
July
4.5
4
1
7
6
August
5.4
6
3
7
7
September
8.4
20
8
5
3
October
11.2
10
13
3
20
November
7.4
2
7
4
11
December
13.2
14
20
5
14
Average
10.2
16.2
8.8
9.1
7.6
9.7
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
11.6
11
11
12
12
12
February
11.0
11
11
12
11
11
March
12.5
12
13
12
13
11
April
12.1
11
13
11
14
May
10.1
10
10
10
11
June
9.8
9
10
10
10
July
9.3
9
10
9
9
August
9.5
10
10
9
10
September
9.8
10
10
11
10
October
10.5
9
10
10
10
November
10.9
10
11
10
11
December
10.9
10
12
10
12
Average
10.7
11.3
10.1
10.8
10.4
10.7
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
308°
289°
301°
312°
290°
February
297°
276°
274°
329°
266°
March
313°
305°
267°
278°
013°
April
171°
281°
281°
295°
May
196°
103°
248°
219°
June
168°
198°
190°
194°
July
193°
188°
192°
187°
August
213°
182°
186°
197°
September
022°
266°
247°
131°
October
276°
352°
260°
314°
November
289°
265°
286°
253°
December
288°
323°
280°
277°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.