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
85.7
71
90
86
89
92
February
86.7
93
90
82
77
90
March
89.6
87
91
82
94
97
April
94.2
93
91
97
93
May
95.6
100
94
97
100
June
94.3
82
96
96
97
July
94.1
87
96
95
98
August
94.7
93
92
96
97
September
93.2
92
85
90
99
October
90.1
85
80
89
93
November
92.9
97
85
95
97
December
87.5
80
79
92
87
Average
91.2
83.5
89.8
88.1
92.7
95.4
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
2.7
3
6
0
2
5
February
5.7
7
8
5
1
6
March
9.3
12
9
11
12
12
April
16.1
19
15
17
14
May
22.0
22
24
22
21
June
26.1
25
26
28
27
July
29.1
29
31
28
31
August
27.7
26
30
28
29
September
23.7
23
23
24
24
October
18.1
18
17
20
18
November
10.0
10
12
10
14
December
5.3
7
5
8
5
Average
15.2
7.1
16.9
16.9
16.4
17.1
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
-5.9
-3
0
-9
-3
-2
February
-3.1
-2
-3
-5
-5
-2
March
-1.9
2
0
0
1
3
April
5.4
7
5
5
4
May
10.7
8
12
10
10
June
14.9
14
15
16
15
July
18.4
19
18
18
20
August
17.7
17
18
19
18
September
14.1
14
14
15
13
October
8.8
9
5
11
9
November
1.4
1
3
1
4
December
-2.8
2
-1
1
-2
Average
6.0
-1.2
7.2
6.5
7.3
7.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
15.4
26
17
13
12
11
February
14.5
9
14
17
23
14
March
14.8
21
18
15
10
9
April
14.0
13
22
11
17
May
10.6
5
10
11
8
June
5.9
6
4
6
3
July
5.6
6
4
6
4
August
5.5
4
4
8
5
September
9.2
10
18
10
3
October
10.8
19
11
9
9
November
10.1
5
14
8
10
December
15.0
18
29
7
13
Average
11.4
19.0
10.5
12.4
9.7
8.1
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
6.7
6
6
6
7
7
February
6.7
7
7
7
6
7
March
7.6
7
8
8
8
7
April
7.5
7
7
8
8
May
5.9
6
6
6
7
June
5.5
5
5
5
6
July
5.0
5
6
5
5
August
4.8
5
5
4
5
September
4.7
5
5
5
5
October
5.4
5
5
5
6
November
6.4
6
6
6
7
December
6.1
5
5
6
7
Average
6.1
6.5
5.7
6.0
5.8
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
278°
286°
303°
312°
285°
February
303°
283°
268°
303°
274°
March
304°
300°
285°
301°
282°
April
264°
295°
294°
308°
May
303°
290°
310°
280°
June
334°
301°
248°
262°
July
257°
251°
272°
259°
August
286°
260°
257°
261°
September
008°
290°
285°
294°
October
280°
271°
259°
262°
November
281°
261°
281°
274°
December
276°
284°
263°
271°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.