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
79.3
76
89
74
83
76
February
74.1
86
61
67
69
85
March
88.7
91
89
83
84
87
April
91.3
80
99
95
81
May
95.9
94
94
97
96
June
94.7
86
92
99
95
July
89.0
79
89
90
92
August
89.6
88
82
90
95
September
87.5
86
88
83
90
October
89.0
76
92
90
87
November
76.8
71
88
54
77
December
73.0
58
69
72
77
Average
87.4
84.7
81.2
85.7
86.8
88.1
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
-7.5
-8
-3
-6
-4
-14
February
-4.8
-2
-4
0
-7
-3
March
1.1
2
1
3
-3
1
April
7.8
5
8
7
8
May
13.9
13
14
14
16
June
18.2
16
21
18
18
July
20.1
19
20
19
21
August
18.4
19
16
18
19
September
13.5
10
13
16
14
October
6.3
4
6
5
6
November
-3.3
0
-2
-9
-4
December
-5.6
-6
-9
-7
-2
Average
5.6
-3.2
6.2
7.4
5.2
6.6
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
-15.0
-18
-11
-14
-12
-24
February
-13.7
-12
-12
-7
-15
-13
March
-11.6
-7
-12
-6
-17
-13
April
-4.8
-6
-4
-6
-3
May
3.2
4
1
3
3
June
8.1
8
9
8
7
July
10.5
11
10
10
10
August
9.4
10
10
8
9
September
5.3
2
6
9
5
October
-2.6
-3
-2
-2
-3
November
-10.1
-6
-10
-16
-12
December
-13.8
-14
-17
-15
-11
Average
-4.3
-13.5
-3.7
-2.3
-5.4
-4.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
8.0
18
14
19
1
0
February
13.9
14
40
28
0
4
March
5.8
20
10
10
1
0
April
5.0
20
2
1
4
May
4.6
10
0
4
4
June
5.7
14
4
6
7
July
12.3
23
22
8
10
August
16.8
24
31
14
11
September
15.2
18
21
6
16
October
10.9
21
13
14
5
November
9.9
39
8
12
2
December
13.8
30
31
22
1
Average
9.6
17.2
20.8
15.4
7.0
5.8
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
2.7
2
3
4
3
2
February
3.4
6
3
5
3
5
March
3.2
4
5
4
3
3
April
3.4
3
4
4
4
May
4.3
5
4
4
4
June
3.2
3
3
4
3
July
2.8
2
4
2
3
August
3.2
4
3
3
3
September
3.4
4
5
1
3
October
3.3
2
5
2
3
November
2.6
5
2
2
3
December
2.5
2
2
3
3
Average
3.3
4.1
3.3
3.6
2.9
3.2
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
043°
102°
133°
030°
032°
February
130°
216°
187°
012°
164°
March
130°
231°
105°
278°
344°
April
251°
299°
308°
287°
May
138°
269°
303°
252°
June
249°
281°
232°
220°
July
274°
171°
260°
264°
August
155°
156°
233°
208°
September
211°
135°
331°
049°
October
017°
143°
072°
102°
November
178°
018°
052°
020°
December
030°
026°
032°
034°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.