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
80.3
77
84
78
68
69
February
85.8
67
78
95
90
91
March
80.9
81
79
73
89
71
April
81.3
68
82
89
89
69
May
79.5
77
77
60
90
74
June
74.2
76
81
58
83
86
July
57.2
41
48
18
67
73
August
79.2
81
100
39
92
90
September
86.9
87
85
90
91
October
91.5
86
84
98
92
November
85.4
87
85
86
96
December
81.2
71
81
76
97
Average
78.7
68.4
78.1
67.5
85.0
82.1
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
-1.9
-1
1
-2
1
-3
February
2.1
1
1
2
3
1
March
1.6
-1
2
1
3
3
April
4.2
3
2
3
5
6
May
6.9
6
5
6
8
8
June
10.2
9
10
9
11
11
July
12.4
11
11
8
13
15
August
13.7
13
12
12
14
14
September
11.5
10
10
11
12
October
6.9
8
7
6
8
November
3.6
5
5
-1
5
December
1.8
-1
3
2
2
Average
6.1
5.1
4.9
5.4
6.3
6.7
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
-4.3
-5
-2
-6
-2
-7
February
-2.1
-3
-3
-2
0
-4
March
-3.6
-4
-2
-3
-2
-2
April
0.3
-1
-3
0
1
2
May
3.2
1
2
2
5
5
June
6.5
5
5
5
7
8
July
8.8
7
8
5
9
11
August
10.2
9
10
9
10
11
September
8.2
7
7
8
8
October
4.0
5
3
3
5
November
0.7
1
1
-4
1
December
-2.3
-4
0
-2
-2
Average
2.6
1.2
1.3
2.0
2.7
2.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
25.1
43
14
13
32
41
February
25.0
45
37
17
14
18
March
25.2
42
36
34
17
26
April
18.6
25
27
14
10
13
May
15.7
21
27
0
9
8
June
15.2
17
27
0
15
20
July
12.8
18
21
0
5
9
August
13.6
18
0
8
11
8
September
19.3
21
25
20
10
October
20.3
20
28
18
19
November
23.2
23
19
29
19
December
27.4
48
27
25
9
Average
19.1
25.4
26.8
13.4
15.4
15.4
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
12.3
16
14
14
15
14
February
12.6
15
15
13
14
15
March
12.7
15
16
14
15
13
April
12.5
14
14
15
13
10
May
12.1
14
14
10
14
9
June
10.3
11
11
11
12
9
July
10.2
9
13
11
11
9
August
12.4
14
17
12
13
12
September
14.2
14
14
14
15
October
13.7
14
18
20
12
November
15.4
14
15
17
19
December
13.6
17
15
16
14
Average
12.4
12.8
13.9
13.1
14.0
12.0
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
097°
305°
031°
020°
058°
February
243°
187°
157°
181°
184°
March
009°
290°
354°
288°
303°
April
303°
311°
121°
102°
190°
May
269°
288°
322°
171°
170°
June
105°
147°
192°
185°
023°
July
267°
236°
252°
275°
320°
August
206°
152°
287°
188°
295°
September
244°
237°
299°
355°
October
004°
276°
282°
224°
November
205°
286°
346°
272°
December
291°
174°
228°
198°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.