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
79.8
78
77
89
68
82
February
78.4
65
66
73
90
81
March
71.9
68
61
54
83
77
April
83.9
83
71
83
85
May
85.1
66
76
90
91
June
77.0
89
53
80
79
July
63.4
49
54
66
72
August
75.6
76
60
87
85
September
85.1
87
89
86
82
October
92.0
91
86
90
98
November
86.4
82
87
84
88
December
78.8
55
74
83
89
Average
78.6
69.3
72.7
69.3
82.2
83.6
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
0.9
2
1
1
1
-2
February
3.3
2
3
4
5
3
March
3.1
1
4
2
4
3
April
5.9
4
5
7
7
May
8.6
7
8
9
10
June
12.0
12
12
12
13
July
14.0
14
13
14
15
August
14.6
15
13
15
15
September
12.6
12
13
14
12
October
8.9
9
9
7
9
November
5.5
6
6
0
5
December
2.5
1
6
4
2
Average
7.0
1.5
7.2
7.6
7.5
7.6
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
-5.8
-4
-6
-4
-4
-7
February
-2.7
-2
-2
-1
0
-2
March
-3.5
-3
-1
-3
-2
-2
April
0.1
-2
-1
1
1
May
2.8
2
2
4
4
June
6.6
6
6
7
7
July
8.9
8
8
9
10
August
9.4
9
9
9
10
September
7.4
7
8
7
6
October
4.0
5
4
3
3
November
1.0
1
2
-4
0
December
-2.1
-4
1
0
-4
Average
1.9
-4.9
2.0
2.6
2.4
2.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
32.1
41
26
24
41
30
February
34.6
44
51
27
31
28
March
35.1
52
42
50
35
29
April
24.9
26
33
24
20
May
23.5
32
14
30
20
June
19.2
23
17
20
19
July
20.3
32
21
15
12
August
20.1
18
30
20
15
September
24.7
30
21
26
26
October
31.7
25
41
54
19
November
32.6
31
33
37
38
December
33.4
44
34
37
23
Average
28.5
46.9
30.7
28.1
29.0
21.9
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
14.5
18
12
14
17
14
February
16.7
17
18
14
18
16
March
15.9
17
18
17
16
17
April
14.1
15
15
15
13
May
13.3
15
12
16
13
June
12.8
13
14
15
11
July
13.6
14
13
14
12
August
13.0
13
13
12
13
September
14.3
14
14
15
14
October
15.4
14
16
20
13
November
14.7
13
15
14
18
December
15.4
18
16
16
12
Average
14.6
17.2
14.6
14.2
15.3
13.6
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
021°
185°
049°
282°
353°
February
246°
182°
155°
138°
157°
March
147°
273°
324°
260°
234°
April
318°
151°
090°
163°
May
284°
315°
141°
139°
June
166°
156°
167°
245°
July
182°
232°
192°
167°
August
173°
289°
205°
230°
September
266°
254°
288°
280°
October
021°
278°
275°
208°
November
205°
225°
328°
249°
December
312°
147°
233°
142°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.