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
71.0
62
57
92
75
66
February
87.2
94
92
95
82
94
March
88.1
97
89
89
89
77
April
91.2
93
92
91
97
90
May
91.2
97
92
92
91
June
93.8
92
95
95
96
July
94.6
96
98
93
98
August
91.4
96
94
93
83
September
91.9
93
96
94
85
October
81.2
90
98
88
94
November
87.7
99
78
99
88
December
84.1
81
71
87
85
Average
88.2
87.3
90.1
91.8
90.7
87.7
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
-4.6
-3
-2
-6
-2
-2
February
-1.8
9
1
-2
-8
-1
March
6.8
11
6
7
10
8
April
14.0
15
15
11
16
14
May
21.7
24
23
21
20
June
27.3
28
28
28
28
July
27.3
27
27
28
29
August
25.7
28
26
27
24
September
24.1
26
23
25
21
October
14.8
17
16
18
13
November
7.8
9
8
9
11
December
2.3
5
1
4
1
Average
13.5
7.8
15.3
13.9
14.2
13.9
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
-11.2
-9
-8
-16
-10
-9
February
-10.1
-4
-8
-13
-16
-11
March
-3.9
-1
-3
-2
0
0
April
2.7
4
3
1
4
2
May
10.4
11
11
10
9
June
16.1
15
15
18
17
July
17.3
16
18
17
19
August
15.3
16
17
16
13
September
12.6
14
12
13
10
October
4.7
6
3
9
2
November
-3.8
-2
-2
-2
0
December
-7.8
-2
-7
-6
-7
Average
3.4
-3.4
4.8
3.4
4.1
3.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
1.7
0
0
0
0
0
February
0.7
0
0
0
0
0
March
1.4
0
0
0
0
0
April
1.6
0
0
0
0
0
May
0.8
0
0
0
0
June
0.9
0
0
0
0
July
0.2
0
0
0
0
August
0.7
0
0
0
0
September
1.1
0
0
0
0
October
1.0
0
0
0
0
November
0.0
0
0
0
0
December
1.5
0
0
0
0
Average
1.0
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
10.5
10
10
12
9
11
February
11.0
12
12
12
10
10
March
11.9
13
12
12
12
11
April
13.3
15
14
16
13
13
May
11.0
11
12
11
11
June
9.3
7
10
8
10
July
6.7
6
8
6
6
August
6.5
7
7
6
6
September
8.1
7
8
7
9
October
9.8
10
10
9
10
November
11.3
9
13
12
12
December
10.7
10
12
11
10
Average
10.2
12.6
9.5
10.9
9.3
9.8
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
289°
291°
276°
348°
278°
February
256°
261°
292°
310°
300°
March
316°
256°
324°
154°
279°
April
311°
255°
241°
274°
296°
May
120°
160°
171°
052°
June
099°
218°
203°
172°
July
290°
226°
200°
192°
August
222°
173°
184°
194°
September
159°
225°
205°
240°
October
290°
244°
021°
287°
November
248°
246°
255°
225°
December
226°
172°
223°
270°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.