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
85.5
80
74
83
89
97
February
85.8
93
89
76
83
86
March
85.5
77
88
76
91
86
April
85.1
80
91
89
90
May
89.8
96
87
91
94
June
90.5
86
91
96
93
July
90.7
79
100
78
94
August
92.7
87
96
88
99
September
90.3
85
87
94
94
October
87.1
86
80
89
88
November
93.3
95
96
99
96
December
85.7
83
86
83
89
Average
88.1
82.9
85.5
87.7
89.1
92.2
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
4.2
4
7
3
3
7
February
5.9
6
6
6
2
7
March
8.3
9
8
10
11
10
April
13.6
14
14
15
10
May
19.8
22
21
21
19
June
24.7
22
24
28
25
July
28.1
28
30
26
28
August
27.5
26
29
29
27
September
23.3
23
22
25
23
October
17.9
19
17
19
16
November
11.2
10
14
11
14
December
6.4
8
8
8
6
Average
14.8
6.0
16.1
16.7
16.4
16.0
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
-3.5
-2
1
-6
-3
0
February
-2.1
-1
-2
-4
-3
0
March
0.8
3
2
1
1
2
April
5.9
7
7
7
4
May
11.0
11
12
12
9
June
16.3
16
16
19
16
July
20.3
21
21
19
20
August
19.9
19
21
22
20
September
16.2
17
15
18
15
October
11.0
12
11
12
9
November
3.8
3
6
4
5
December
0.0
2
1
1
-1
Average
7.4
-1.7
9.0
8.5
9.0
8.3
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
20
27
17
10
5
February
14.0
5
14
21
21
14
March
14.4
20
18
17
5
12
April
15.4
12
10
11
23
May
8.0
6
4
9
4
June
7.8
14
7
3
4
July
6.2
10
4
13
2
August
5.2
10
3
8
4
September
8.9
18
11
9
4
October
11.6
10
10
10
17
November
10.3
7
9
5
11
December
14.9
19
17
13
13
Average
11.1
15.3
13.1
9.8
9.5
8.8
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
10.8
10
9
11
10
11
February
10.5
10
11
11
9
10
March
11.9
12
13
10
11
12
April
11.6
11
12
12
13
May
10.4
11
10
11
11
June
9.4
9
10
9
9
July
9.0
8
10
9
9
August
9.0
9
10
8
9
September
9.4
9
9
9
10
October
9.9
8
9
10
10
November
10.1
10
10
9
10
December
10.0
9
13
9
10
Average
10.2
10.7
9.6
10.3
9.7
10.2
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
304°
307°
292°
308°
275°
February
287°
294°
270°
311°
270°
March
328°
338°
279°
270°
022°
April
067°
292°
323°
332°
May
299°
090°
339°
269°
June
095°
168°
223°
172°
July
158°
216°
018°
175°
August
198°
171°
140°
198°
September
039°
310°
245°
157°
October
271°
011°
026°
246°
November
276°
252°
270°
252°
December
293°
312°
277°
273°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.