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
62.3
48
47
66
64
79
February
76.7
89
75
70
76
81
March
77.2
64
67
73
91
80
April
88.8
89
87
89
89
May
89.1
90
88
90
92
June
89.2
78
90
93
95
July
91.3
82
89
87
93
August
92.4
88
94
91
95
September
91.3
88
85
95
94
October
85.3
88
91
80
83
November
82.2
85
74
88
86
December
77.8
78
69
80
74
Average
82.5
65.6
79.5
82.2
86.1
87.6
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
1.0
1
4
-2
0
3
February
4.2
7
8
3
-1
2
March
7.5
11
6
9
12
10
April
13.9
16
13
15
11
May
20.2
20
22
19
18
June
24.3
24
25
25
25
July
26.5
26
27
25
28
August
25.4
25
26
27
26
September
22.6
23
21
23
22
October
16.4
16
15
19
15
November
8.1
10
10
8
12
December
3.9
7
3
7
3
Average
13.5
6.3
15.4
14.6
14.8
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
-6.8
-4
-1
-9
-4
-3
February
-5.9
-1
-3
-6
-7
-4
March
-2.8
1
-1
-1
0
1
April
3.9
5
3
5
2
May
9.9
8
11
9
9
June
14.8
14
14
17
15
July
17.2
15
17
17
18
August
16.6
16
17
18
16
September
13.7
14
13
14
12
October
8.0
9
6
11
7
November
0.9
2
3
1
4
December
-2.2
2
-2
0
-3
Average
5.1
-2.7
6.6
5.8
6.6
6.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
30.5
38
35
39
19
23
February
22.5
9
22
37
22
20
March
21.0
22
31
33
7
13
April
13.6
12
20
9
14
May
10.5
11
10
11
11
June
7.2
7
8
6
4
July
4.9
7
6
7
3
August
4.6
7
3
6
4
September
5.8
7
13
4
3
October
10.5
10
10
12
10
November
17.6
13
27
15
13
December
18.3
18
21
15
16
Average
14.3
23.6
14.6
17.8
10.3
10.3
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
7.0
7
6
8
6
7
February
7.5
7
8
8
7
7
March
7.7
7
8
9
8
7
April
7.2
7
7
7
7
May
6.2
6
6
6
7
June
5.7
6
6
6
6
July
5.3
5
6
5
5
August
4.9
5
5
4
5
September
5.1
4
5
6
5
October
6.2
6
7
5
6
November
7.1
7
7
7
8
December
6.6
6
6
7
7
Average
6.4
6.9
6.0
6.6
6.1
6.3
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
244°
246°
268°
260°
246°
February
261°
248°
245°
269°
255°
March
281°
268°
257°
264°
245°
April
252°
255°
272°
288°
May
318°
261°
297°
275°
June
310°
273°
238°
267°
July
268°
260°
281°
282°
August
283°
260°
262°
274°
September
348°
275°
248°
243°
October
251°
242°
244°
243°
November
243°
236°
233°
237°
December
234°
231°
227°
240°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.