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
70.4
56
49
87
69
72
February
84.9
96
83
84
87
94
March
84.6
86
80
80
90
80
April
84.8
88
83
83
84
88
May
91.6
93
93
89
97
June
95.1
94
95
98
96
July
94.4
94
95
96
95
August
91.7
91
92
90
94
September
89.1
88
95
95
89
October
85.7
82
94
82
91
November
83.0
89
73
92
89
December
67.4
66
68
71
73
Average
85.8
82.5
84.1
87.2
87.9
88.9
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
-5.5
-4
-4
-8
-3
-2
February
-3.9
4
-2
-5
-6
-2
March
3.6
6
2
2
8
5
April
9.7
12
9
7
12
10
May
19.1
20
19
19
18
June
24.5
25
22
26
25
July
26.1
24
25
27
27
August
24.1
24
24
26
25
September
20.0
21
20
22
19
October
11.8
11
13
16
8
November
3.5
5
5
5
8
December
-2.8
2
-2
-1
-1
Average
10.2
4.2
11.5
9.6
12.6
11.6
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
-12.4
-9
-9
-17
-10
-9
February
-13.2
-8
-11
-16
-17
-13
March
-7.7
-5
-8
-7
-3
-3
April
-1.3
0
-1
-1
1
-2
May
6.8
7
8
7
7
June
12.4
12
10
15
13
July
14.4
13
14
14
16
August
13.5
13
14
15
14
September
10.5
12
9
10
9
October
3.5
4
3
7
1
November
-4.2
-4
-3
-3
-1
December
-9.7
-4
-9
-9
-8
Average
0.4
-6.5
1.9
-1.9
2.3
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
18.2
18
26
16
14
24
February
16.9
9
18
23
15
14
March
12.4
18
19
14
9
12
April
14.4
12
19
21
14
12
May
8.5
7
10
7
6
June
5.4
3
7
5
5
July
3.6
2
4
3
6
August
4.8
3
2
6
6
September
6.9
8
6
2
7
October
13.4
15
15
2
14
November
16.8
10
25
15
10
December
19.8
11
32
23
12
Average
11.5
14.1
11.0
13.4
8.8
9.9
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
5.8
6
5
8
5
5
February
6.6
7
7
7
7
7
March
7.2
8
7
8
8
7
April
7.5
9
8
8
7
7
May
6.4
6
7
7
7
June
6.1
5
6
6
7
July
5.3
5
6
5
5
August
5.3
5
6
6
6
September
6.1
6
6
6
6
October
6.8
7
7
6
7
November
7.0
7
7
8
8
December
5.9
5
6
7
5
Average
6.4
7.3
6.1
6.9
6.2
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
279°
295°
263°
302°
265°
February
252°
281°
286°
277°
280°
March
306°
340°
307°
274°
276°
April
320°
278°
181°
319°
316°
May
185°
188°
239°
336°
June
032°
282°
259°
215°
July
300°
266°
317°
263°
August
301°
261°
231°
256°
September
164°
254°
255°
260°
October
305°
248°
310°
269°
November
255°
250°
260°
242°
December
227°
167°
229°
267°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.