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
73.7
57
80
64
82
90
February
87.5
88
95
97
86
96
March
98.2
99
100
99
100
99
April
96.1
99
98
94
98
100
May
94.7
100
98
70
100
June
99.6
99
99
100
100
July
99.9
100
100
100
100
August
95.5
90
100
94
98
September
93.1
96
100
100
73
October
95.1
100
99
89
100
November
84.4
76
82
91
92
December
75.4
69
52
95
77
Average
91.2
85.8
92.0
91.5
92.1
93.9
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
5.4
2
7
4
9
9
February
8.3
11
9
11
8
12
March
14.1
16
13
16
16
14
April
18.8
19
18
15
22
21
May
25.4
28
21
25
25
June
29.9
30
28
33
29
July
35.1
35
36
37
34
August
33.8
33
36
33
33
September
27.0
26
29
28
28
October
19.0
19
22
19
20
November
9.2
5
7
12
11
December
5.5
7
2
6
6
Average
18.5
12.0
19.3
19.3
20.7
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
-2.5
-3
-1
-2
1
1
February
-2.6
2
-2
-2
0
0
March
1.4
2
0
4
1
2
April
4.5
4
4
3
4
5
May
9.3
11
8
9
9
June
13.5
13
13
16
14
July
16.3
16
17
19
15
August
15.1
16
16
15
14
September
10.8
11
11
11
11
October
5.3
6
7
7
7
November
0.6
1
-1
4
1
December
-1.1
2
-4
-1
0
Average
5.5
0.9
6.5
6.0
7.0
6.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
10.3
16
6
5
10
10
February
10.2
13
9
4
12
4
March
5.2
4
3
7
3
3
April
6.0
4
6
10
6
1
May
4.3
3
9
2
5
June
3.1
2
6
1
6
July
0.3
0
1
1
1
August
0.8
3
1
0
1
September
2.0
6
1
5
0
October
5.9
10
3
9
9
November
6.6
8
9
9
7
December
7.7
8
17
11
6
Average
5.4
9.1
5.1
5.6
5.0
4.2
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
4.5
5
4
4
4
7
February
6.9
5
8
6
9
8
March
6.8
7
7
6
7
8
April
8.1
8
7
9
8
8
May
7.2
7
8
8
9
June
7.6
7
8
7
9
July
7.0
7
6
7
8
August
6.4
7
6
7
6
September
5.8
6
6
6
5
October
5.6
5
5
6
8
November
5.1
4
5
6
6
December
4.3
4
4
7
5
Average
6.4
6.2
6.1
6.0
6.9
7.4
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
243°
025°
250°
203°
245°
February
255°
252°
267°
252°
255°
March
254°
252°
257°
251°
249°
April
251°
248°
259°
265°
264°
May
250°
246°
263°
252°
June
252°
248°
264°
252°
July
262°
261°
261°
259°
August
251°
258°
259°
260°
September
254°
259°
261°
288°
October
276°
247°
256°
252°
November
257°
252°
245°
252°
December
224°
156°
234°
240°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.