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
76.5
61
68
93
77
66
February
87.4
86
87
90
86
95
March
86.1
90
76
96
86
84
April
89.7
91
91
95
95
May
92.4
93
97
92
92
June
97.1
98
96
100
99
July
96.8
95
98
90
100
August
95.5
95
94
98
97
September
93.4
94
99
96
96
October
88.8
84
98
91
89
November
91.7
99
92
93
90
December
82.8
80
62
96
89
Average
89.2
79.2
88.6
93.4
91.8
91.5
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
-3.9
-3
-3
0
0
-2
February
0.0
8
0
1
-6
1
March
7.3
11
2
8
12
10
April
14.2
16
13
16
16
May
21.8
26
22
22
20
June
29.4
31
29
32
30
July
30.0
30
31
31
31
August
28.4
31
30
29
30
September
25.6
28
27
26
25
October
15.6
17
19
18
13
November
8.2
12
7
10
11
December
2.0
6
-2
4
3
Average
13.8
5.4
16.4
16.1
16.2
15.4
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
-11.0
-11
-12
-13
-6
-10
February
-11.5
-3
-12
-12
-15
-9
March
-3.1
-2
-6
-3
0
-1
April
2.0
3
1
3
1
May
10.1
12
10
10
10
June
17.1
18
17
17
18
July
18.7
17
20
19
20
August
17.4
19
18
19
18
September
13.7
15
13
14
12
October
4.4
6
5
7
2
November
-3.2
-1
-4
-2
-1
December
-8.7
-3
-10
-7
-7
Average
2.9
-6.4
4.7
3.8
5.0
4.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
14.8
25
22
13
14
15
February
13.6
6
14
13
15
3
March
13.5
13
19
6
15
13
April
13.6
16
16
8
7
May
8.8
5
4
10
12
June
4.2
3
5
2
3
July
2.9
4
4
6
1
August
4.2
4
6
1
1
September
4.9
3
3
5
5
October
9.8
9
3
9
10
November
9.1
4
15
7
6
December
14.4
11
35
9
9
Average
9.7
14.5
9.2
8.8
7.9
6.8
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
9.3
9
8
10
9
10
February
10.0
10
10
12
8
10
March
11.4
12
12
12
12
12
April
12.1
13
15
12
11
May
9.5
9
10
10
10
June
8.8
7
9
8
10
July
7.9
7
9
8
8
August
8.3
9
8
9
9
September
9.3
8
9
10
10
October
10.2
10
10
9
10
November
10.3
10
12
10
10
December
9.5
8
12
10
10
Average
9.8
10.2
9.3
10.6
9.5
9.9
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
303°
329°
290°
318°
293°
February
286°
352°
319°
291°
311°
March
002°
358°
353°
141°
071°
April
322°
302°
333°
313°
May
130°
210°
136°
011°
June
144°
215°
183°
168°
July
199°
235°
153°
168°
August
156°
163°
151°
182°
September
163°
171°
171°
244°
October
320°
260°
164°
301°
November
263°
286°
278°
235°
December
293°
306°
313°
290°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.