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
84.8
73
78
85
94
92
February
83.4
89
81
80
79
82
March
87.5
86
89
77
89
89
April
89.2
81
95
95
93
May
91.2
96
88
94
92
June
93.4
92
93
95
96
July
92.8
87
98
85
96
August
93.3
89
93
94
97
September
90.2
78
90
96
92
October
88.1
89
87
86
83
November
93.5
94
93
98
92
December
82.3
69
85
83
85
Average
88.9
82.8
85.8
89.1
90.8
91.4
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
3.1
3
6
1
2
5
February
5.5
7
7
6
2
6
March
9.4
12
10
10
11
12
April
15.6
18
16
17
13
May
22.0
23
24
22
21
June
26.8
26
27
28
28
July
29.9
30
31
27
31
August
28.6
27
30
29
30
September
24.3
25
24
24
24
October
18.5
20
18
19
17
November
10.8
10
14
11
14
December
5.4
8
7
8
6
Average
15.6
7.2
17.3
17.6
16.7
17.2
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
-5.2
-3
-1
-8
-5
-3
February
-4.3
-3
-4
-5
-5
-3
March
-1.6
3
0
0
0
1
April
4.8
6
5
5
3
May
10.1
8
12
10
9
June
15.0
15
15
16
15
July
18.9
20
19
18
20
August
17.9
17
19
19
18
September
13.9
15
14
14
13
October
8.5
9
7
10
8
November
1.0
0
4
0
3
December
-3.8
1
-1
0
-2
Average
5.7
-1.0
7.2
6.9
6.9
6.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
15.3
23
22
16
8
8
February
15.7
10
17
20
24
15
March
13.4
18
15
15
7
13
April
16.5
13
13
13
21
May
9.3
6
5
11
5
June
6.5
5
7
6
4
July
6.7
10
4
15
3
August
5.9
13
2
8
5
September
9.6
19
11
11
5
October
12.9
12
8
12
17
November
10.4
8
11
6
11
December
15.7
18
17
12
14
Average
11.6
16.8
12.6
10.0
10.7
9.4
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
7.7
7
7
8
8
7
February
8.2
8
9
9
8
7
March
9.2
9
9
8
9
8
April
8.9
8
10
9
11
May
7.8
7
8
8
9
June
7.0
7
7
7
7
July
6.3
6
7
6
7
August
6.4
6
7
6
7
September
6.5
7
6
7
7
October
7.0
6
7
7
7
November
7.6
7
8
7
8
December
7.1
6
9
6
8
Average
7.5
8.2
6.9
7.6
7.3
7.8
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
309°
323°
310°
318°
289°
February
306°
304°
280°
328°
289°
March
326°
319°
297°
287°
326°
April
279°
299°
307°
307°
May
299°
115°
304°
270°
June
291°
250°
212°
233°
July
199°
228°
301°
225°
August
251°
226°
206°
249°
September
356°
305°
250°
242°
October
282°
347°
346°
274°
November
295°
262°
277°
265°
December
314°
329°
299°
287°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.