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
66.7
50
55
88
66
62
February
81.0
81
73
88
81
84
March
78.5
83
68
81
80
74
April
83.3
89
82
86
96
May
87.1
90
91
86
83
June
94.3
95
92
99
97
July
95.2
93
92
92
99
August
91.4
91
88
95
95
September
90.9
89
97
95
96
October
85.0
74
100
85
89
November
86.7
95
88
90
87
December
74.7
69
50
95
83
Average
83.6
70.9
81.7
87.5
87.9
87.7
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
-4.4
-4
-4
-3
-1
-4
February
-2.5
7
-1
-2
-6
-2
March
5.0
9
1
5
10
7
April
11.9
13
10
14
14
May
20.7
24
21
20
18
June
27.7
28
27
30
29
July
27.7
27
28
28
29
August
26.1
28
27
27
27
September
23.8
26
25
25
22
October
13.9
15
17
17
11
November
6.3
10
6
8
9
December
0.2
5
-3
2
2
Average
11.9
3.7
13.7
13.7
14.4
13.5
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
-13.6
-12
-12
-16
-8
-12
February
-12.3
-5
-12
-14
-16
-11
March
-5.8
-4
-8
-4
-1
-2
April
1.0
1
0
2
0
May
9.3
11
9
9
9
June
16.2
16
16
16
17
July
17.0
15
18
17
18
August
15.8
16
16
17
17
September
12.5
16
11
12
10
October
3.5
5
4
7
1
November
-4.4
-2
-4
-2
-1
December
-9.6
-4
-10
-8
-9
Average
1.6
-8.8
2.9
2.5
3.8
3.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
18.4
21
25
15
15
24
February
17.0
14
22
18
14
9
March
13.8
11
27
11
8
10
April
13.5
17
20
5
8
May
8.4
5
5
6
11
June
3.9
4
5
2
2
July
3.0
3
4
5
2
August
4.3
9
5
1
1
September
4.7
0
3
3
6
October
10.2
15
1
7
8
November
10.0
7
21
8
7
December
14.3
12
29
10
8
Average
10.4
15.3
12.6
10.3
6.4
7.5
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
12.0
11
11
13
12
12
February
12.9
13
14
15
10
13
March
13.3
14
13
15
13
13
April
13.8
16
17
14
12
May
11.7
11
13
12
12
June
10.3
8
11
9
12
July
8.2
8
9
7
8
August
8.3
8
8
8
9
September
9.7
11
9
9
11
October
11.7
12
12
11
12
November
13.0
13
14
13
13
December
11.9
11
13
13
12
Average
11.4
12.8
11.2
12.4
10.8
11.5
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
287°
308°
276°
297°
280°
February
263°
300°
310°
272°
285°
March
338°
339°
341°
182°
295°
April
303°
278°
319°
309°
May
142°
216°
177°
359°
June
156°
226°
234°
179°
July
275°
242°
183°
184°
August
242°
198°
169°
199°
September
185°
197°
217°
245°
October
315°
259°
222°
281°
November
244°
270°
266°
241°
December
259°
231°
272°
276°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.