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
82.3
77
78
75
91
83
February
82.2
91
78
78
88
80
March
85.9
75
79
87
93
96
April
89.6
92
90
90
88
83
May
95.3
95
95
97
97
June
91.3
84
88
96
93
July
87.8
73
90
87
91
August
86.2
84
83
87
89
September
85.7
76
78
89
92
October
87.4
84
82
90
93
November
89.6
91
86
91
94
December
82.9
65
82
86
91
Average
87.3
83.6
81.8
85.0
90.3
90.2
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
-2.3
-2
1
-4
-3
1
February
0.3
2
0
0
-2
1
March
4.2
5
4
5
7
6
April
11.0
12
13
11
13
9
May
19.4
20
23
19
19
June
23.7
22
23
26
25
July
26.6
27
27
23
28
August
25.4
23
27
26
25
September
21.8
23
20
21
22
October
15.1
16
17
16
13
November
6.1
5
9
7
10
December
0.7
2
3
3
2
Average
11.7
4.0
12.7
13.8
13.1
13.4
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
-6
-19
-10
-10
February
-13.7
-11
-12
-13
-13
-13
March
-8.8
-4
-5
-6
-8
-5
April
-1.4
-1
0
0
-1
-2
May
4.5
3
6
5
4
June
9.8
11
10
12
10
July
13.2
15
11
13
15
August
12.7
12
14
15
12
September
8.7
10
9
10
6
October
3.3
5
1
5
2
November
-5.7
-4
-2
-4
-3
December
-9.2
-6
-6
-8
-6
Average
-1.7
-7.7
1.7
0.5
1.2
0.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
21.8
28
28
23
19
20
February
21.5
16
27
28
17
22
March
18.8
28
28
20
14
9
April
18.3
20
12
25
21
23
May
9.8
11
7
8
7
June
11.4
22
10
4
12
July
8.7
17
6
15
5
August
6.6
12
6
7
5
September
7.3
12
14
7
2
October
14.4
19
10
16
15
November
17.1
15
23
12
15
December
21.4
26
22
19
21
Average
14.9
22.9
18.4
14.8
12.7
12.1
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
3.7
4
3
4
4
3
February
4.4
4
4
5
4
4
March
5.3
5
5
5
6
6
April
5.3
6
6
6
5
6
May
4.8
6
5
4
5
June
4.0
3
4
4
4
July
3.1
3
3
3
3
August
3.2
3
3
3
3
September
3.3
2
3
4
5
October
3.7
3
3
3
4
November
3.9
4
5
4
4
December
3.5
3
4
4
4
Average
4.1
4.6
3.8
4.0
4.0
4.3
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
308°
313°
316°
317°
316°
February
305°
293°
273°
292°
294°
March
303°
313°
278°
283°
254°
April
105°
181°
295°
316°
291°
May
326°
183°
308°
295°
June
058°
227°
199°
282°
July
175°
261°
312°
179°
August
224°
281°
159°
270°
September
329°
311°
186°
198°
October
173°
190°
287°
215°
November
290°
277°
283°
277°
December
328°
281°
301°
252°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.