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
84.0
76
74
81
91
90
February
84.1
91
86
83
84
84
March
83.9
76
85
79
88
88
April
82.0
74
87
93
89
May
88.4
93
82
95
93
June
84.6
69
86
96
85
July
86.5
66
99
87
84
August
87.5
81
88
81
94
September
90.2
91
87
92
86
October
83.8
82
79
86
86
November
89.2
91
90
98
89
December
79.7
69
82
78
81
Average
85.1
80.9
79.4
85.7
89.3
87.5
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
1.4
1
4
-1
2
3
February
2.7
4
3
3
0
3
March
6.0
7
6
7
8
9
April
11.5
11
12
13
10
May
17.7
19
18
18
18
June
22.9
20
22
26
24
July
26.3
26
28
24
27
August
25.9
24
27
26
27
September
21.9
22
21
22
23
October
15.6
17
16
16
15
November
8.5
8
11
9
11
December
3.6
6
5
4
4
Average
12.5
3.9
13.8
14.3
14.0
14.5
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
-7.5
-6
-3
-10
-5
-5
February
-6.0
-5
-7
-7
-7
-5
March
-3.6
0
-1
-2
-3
-1
April
2.9
4
3
3
2
May
8.1
8
9
9
8
June
13.3
13
13
15
14
July
17.3
18
17
16
19
August
16.7
16
17
18
17
September
12.9
14
11
14
13
October
7.2
9
6
8
6
November
0.0
-1
2
0
2
December
-5.9
-1
-2
-3
-3
Average
3.9
-4.5
5.5
5.0
5.4
5.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
15.1
20
22
20
13
12
February
13.8
4
15
15
19
16
March
11.7
19
12
11
5
11
April
14.2
13
12
12
16
May
6.7
6
4
7
4
June
8.6
16
6
4
6
July
6.6
14
4
14
2
August
5.4
14
5
4
3
September
5.2
7
10
5
3
October
10.4
10
8
9
13
November
12.0
9
12
6
10
December
15.1
14
20
17
11
Average
10.4
14.3
12.5
9.4
8.9
8.3
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
9
8
7
February
8.1
9
8
8
7
8
March
9.3
10
9
8
9
9
April
9.3
9
10
9
10
May
8.4
9
8
8
10
June
7.3
7
7
8
7
July
6.5
6
7
6
7
August
6.5
7
7
6
7
September
6.8
6
7
7
8
October
6.9
6
6
6
7
November
7.6
7
8
7
7
December
7.3
6
10
6
8
Average
7.7
8.5
7.3
7.8
7.4
7.9
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
324°
339°
320°
331°
311°
February
305°
315°
290°
317°
287°
March
322°
322°
297°
275°
347°
April
074°
314°
320°
320°
May
274°
138°
300°
256°
June
098°
192°
219°
144°
July
156°
213°
007°
182°
August
197°
165°
157°
201°
September
045°
290°
225°
198°
October
294°
140°
030°
277°
November
287°
259°
279°
278°
December
310°
327°
296°
283°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.