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
80.8
67
78
62
91
87
February
82.8
86
95
71
86
87
March
92.5
79
85
93
96
100
April
96.6
95
95
93
100
100
May
96.1
100
89
99
97
June
99.2
99
99
99
98
July
99.6
100
100
100
100
August
98.7
94
100
99
99
September
97.4
100
99
99
100
October
94.2
89
99
97
100
November
92.6
86
90
99
92
December
82.6
83
85
84
89
Average
92.2
81.8
92.2
90.5
96.1
96.0
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
1.8
2
0
-2
4
3
February
4.0
7
3
0
5
7
March
10.1
10
4
12
12
12
April
15.7
16
14
14
17
17
May
21.2
23
19
22
22
June
27.3
24
27
32
26
July
33.2
33
34
35
32
August
31.3
31
33
30
32
September
25.8
25
28
27
28
October
16.6
17
19
17
18
November
8.7
8
4
11
9
December
2.4
5
0
4
4
Average
15.6
8.6
15.6
16.2
18.0
17.4
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
-5.5
-4
-5
-8
-3
-2
February
-4.1
-1
-6
-8
-3
-4
March
-1.5
-1
-4
0
-1
1
April
2.7
3
1
1
3
3
May
7.5
9
6
7
8
June
11.7
11
12
15
11
July
16.8
17
18
18
15
August
15.1
14
17
14
16
September
10.4
11
12
10
11
October
3.8
5
5
6
5
November
-1.1
-1
-5
2
-1
December
-5.9
-2
-6
-3
-5
Average
3.9
-1.2
4.1
3.9
5.3
4.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
10.7
23
9
8
5
10
February
8.5
11
6
8
6
4
March
8.1
16
18
5
4
5
April
6.0
4
7
14
4
1
May
6.1
3
13
1
5
June
2.7
2
4
1
6
July
0.7
0
0
1
1
August
1.5
4
3
1
1
September
1.4
3
1
3
0
October
8.9
29
4
11
1
November
7.1
10
7
5
8
December
9.6
10
15
17
4
Average
6.4
13.5
8.2
6.5
4.5
3.5
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
10.5
12
10
10
10
11
February
10.8
11
13
10
13
12
March
10.9
10
12
11
11
11
April
12.1
13
13
12
12
11
May
9.3
9
11
10
10
June
8.9
8
10
9
10
July
7.0
7
6
7
8
August
7.2
8
7
8
8
September
7.4
7
8
8
7
October
9.2
9
9
9
10
November
9.2
8
10
9
9
December
9.4
10
9
10
9
Average
9.5
11.3
9.5
9.4
9.5
9.5
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
355°
033°
078°
058°
328°
February
279°
002°
064°
274°
286°
March
275°
310°
274°
275°
269°
April
259°
263°
275°
290°
271°
May
130°
269°
266°
269°
June
247°
267°
247°
262°
July
261°
266°
211°
272°
August
129°
168°
261°
268°
September
232°
133°
270°
288°
October
268°
250°
257°
272°
November
019°
277°
346°
043°
December
074°
058°
255°
054°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.