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
92.4
92
88
95
93
96
February
87.3
86
89
94
75
93
March
87.4
92
85
95
88
76
April
94.7
96
94
98
92
94
May
91.4
91
93
93
89
June
96.9
93
98
98
99
July
96.0
95
97
96
95
August
97.6
99
97
100
99
September
96.4
96
96
99
96
October
92.5
91
99
94
89
November
92.8
96
94
94
98
December
93.2
96
82
96
98
Average
92.8
91.6
92.7
95.4
93.4
93.4
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
3.4
2
-1
5
5
6
February
3.7
9
2
5
-3
6
March
9.9
12
6
11
11
9
April
16.7
17
17
17
17
16
May
20.3
22
21
19
19
June
28.3
25
29
29
30
July
31.6
30
33
32
32
August
31.0
31
33
31
32
September
27.3
27
29
28
26
October
16.2
18
19
18
13
November
11.6
13
9
14
14
December
6.4
8
3
9
6
Average
16.0
9.8
16.5
18.1
17.8
17.9
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
-9.7
-11
-10
-9
-5
-7
February
-9.2
-4
-9
-10
-13
-8
March
-4.3
-3
-5
-5
-3
-3
April
-1.7
2
0
-1
0
-2
May
6.7
9
5
6
7
June
13.0
13
12
14
13
July
16.2
15
18
16
16
August
14.3
14
15
14
15
September
9.8
10
10
10
7
October
0.8
2
2
3
-2
November
-4.2
-3
-7
-1
-3
December
-7.5
-5
-10
-6
-7
Average
1.4
-4.0
2.6
2.0
3.2
2.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.0
12
19
11
3
6
February
16.7
13
13
9
35
14
March
11.2
10
11
12
11
12
April
8.0
10
7
3
9
12
May
6.7
6
6
11
4
June
3.0
5
1
3
3
July
3.0
3
3
1
4
August
1.0
2
0
1
0
September
1.2
1
2
1
2
October
5.9
7
1
7
7
November
5.4
6
6
1
0
December
8.4
7
22
2
6
Average
7.1
11.1
6.8
5.6
6.9
5.5
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
11.7
10
9
13
15
13
February
12.1
11
12
14
10
14
March
11.9
11
12
13
11
12
April
13.7
14
12
18
13
12
May
11.3
11
11
11
12
June
9.3
9
9
9
11
July
8.9
8
9
9
10
August
9.0
9
9
9
9
September
9.6
9
9
9
9
October
11.7
10
11
11
13
November
12.0
12
12
12
11
December
12.3
13
14
12
12
Average
11.2
11.6
10.4
11.7
10.7
11.3
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
320°
310°
309°
325°
310°
February
303°
305°
308°
296°
325°
March
334°
311°
331°
327°
293°
April
315°
320°
313°
335°
326°
May
154°
305°
147°
145°
June
151°
267°
153°
300°
July
038°
143°
153°
159°
August
276°
170°
188°
158°
September
331°
227°
328°
316°
October
321°
322°
327°
298°
November
314°
319°
309°
288°
December
313°
309°
277°
327°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.