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
69.5
61
58
79
71
67
February
79.4
72
74
85
77
82
March
80.4
85
61
89
90
86
April
83.5
80
82
74
89
95
May
91.3
88
91
95
93
June
96.8
98
99
99
97
July
95.5
95
94
88
100
August
92.9
93
91
95
95
September
90.5
90
91
94
96
October
88.6
83
97
90
88
November
86.0
94
78
90
94
December
73.3
65
52
89
79
Average
85.4
74.8
82.3
86.3
89.5
90.3
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
-6.9
-6
-6
-6
-2
-5
February
-4.3
4
-3
-3
-8
-3
March
3.4
6
-2
4
9
5
April
10.9
14
10
8
13
12
May
20.0
24
19
20
18
June
27.3
28
27
30
28
July
28.0
28
28
29
29
August
26.3
28
27
28
28
September
23.0
25
25
24
21
October
12.7
14
16
16
10
November
5.0
8
3
7
9
December
-1.0
4
-3
-1
1
Average
11.3
4.5
13.2
12.6
13.7
12.6
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
-14.0
-13
-14
-18
-9
-14
February
-14.2
-6
-14
-17
-17
-14
March
-6.0
-5
-11
-6
-2
-4
April
-1.7
2
-1
-1
0
-1
May
8.3
10
9
8
8
June
15.3
16
15
16
17
July
16.7
15
17
17
18
August
15.3
16
16
16
16
September
11.5
13
11
12
10
October
2.5
3
3
6
1
November
-5.3
-3
-5
-3
-3
December
-10.3
-5
-12
-11
-9
Average
0.8
-6.5
2.2
1.4
2.8
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
9.6
14
10
12
7
10
February
9.9
9
19
12
7
4
March
9.5
17
21
4
4
3
April
11.2
14
21
17
7
5
May
5.3
3
3
5
8
June
3.1
3
1
2
6
July
3.0
1
5
4
1
August
3.1
5
4
1
1
September
4.4
5
1
7
7
October
7.2
10
3
8
7
November
8.6
8
21
7
1
December
10.9
14
31
9
7
Average
7.5
13.6
9.7
8.4
5.4
4.9
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
10.1
10
9
11
10
10
February
10.6
9
12
13
9
10
March
11.3
13
12
12
11
11
April
12.3
13
13
15
12
11
May
10.0
10
11
10
10
June
9.3
8
10
8
11
July
8.3
8
9
8
9
August
8.5
9
9
9
9
September
9.4
8
9
10
10
October
11.0
11
11
10
11
November
10.7
10
12
10
11
December
10.2
9
12
10
10
Average
10.2
11.5
9.8
11.1
9.7
10.1
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
285°
319°
287°
299°
246°
February
274°
339°
309°
250°
284°
March
350°
007°
341°
168°
236°
April
332°
333°
312°
335°
310°
May
141°
215°
183°
360°
June
152°
227°
206°
162°
July
287°
239°
164°
194°
August
217°
210°
168°
181°
September
138°
195°
203°
259°
October
314°
266°
227°
272°
November
268°
292°
262°
232°
December
285°
310°
282°
288°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.