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
85.3
79
78
79
95
92
February
83.7
84
88
75
82
87
March
86.3
82
89
73
87
88
April
87.4
77
92
94
92
May
89.8
93
85
95
89
June
89.6
86
92
92
90
July
89.3
80
93
85
93
August
89.6
87
90
92
87
September
85.1
74
83
90
90
October
85.9
85
79
89
84
November
91.1
92
87
95
91
December
83.4
68
89
84
89
Average
86.9
81.4
83.1
85.0
90.1
89.2
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
3.8
3
8
1
3
6
February
5.8
6
6
6
3
6
March
9.1
11
9
10
11
11
April
15.0
17
15
16
12
May
21.2
21
22
21
20
June
25.7
24
25
27
27
July
28.7
29
29
26
30
August
27.4
26
29
28
27
September
23.5
23
23
23
24
October
18.2
19
18
19
17
November
10.9
10
13
11
14
December
5.8
8
7
8
6
Average
15.1
6.4
16.7
16.7
16.2
16.6
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
-5.1
-4
-1
-9
-5
-4
February
-5.9
-4
-5
-6
-5
-3
March
-1.0
1
-1
-1
-1
1
April
4.3
5
4
4
3
May
9.3
7
11
9
9
June
14.2
13
13
16
15
July
18.2
19
18
17
19
August
17.1
16
18
18
16
September
12.9
14
12
14
12
October
7.8
8
6
9
7
November
0.0
-2
2
-1
2
December
-3.2
0
-2
-2
-3
Average
5.0
-2.0
6.2
5.9
6.1
6.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.7
21
18
12
3
6
February
11.5
8
12
17
17
11
March
11.6
17
17
10
5
8
April
12.3
11
9
10
16
May
7.1
5
5
8
5
June
5.7
5
7
4
4
July
6.1
10
4
11
3
August
5.4
11
3
7
5
September
9.2
22
11
9
4
October
9.5
10
8
7
13
November
9.4
10
12
6
10
December
12.6
14
17
7
14
Average
9.6
14.9
11.8
8.7
7.8
7.7
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
6.2
6
5
6
6
6
February
6.4
6
6
6
6
6
March
7.5
8
8
6
7
7
April
7.3
6
8
8
9
May
6.4
6
7
6
7
June
5.4
5
5
5
5
July
4.8
4
5
5
5
August
4.9
5
5
5
5
September
5.2
5
5
5
6
October
5.5
4
5
6
5
November
5.7
5
6
5
6
December
5.7
5
8
5
6
Average
6.0
6.5
5.3
5.9
5.8
6.1
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°
317°
308°
317°
298°
February
295°
304°
270°
331°
285°
March
334°
323°
284°
286°
328°
April
265°
292°
306°
311°
May
284°
117°
311°
288°
June
197°
239°
218°
240°
July
201°
227°
300°
205°
August
255°
232°
213°
220°
September
019°
322°
269°
247°
October
296°
017°
002°
275°
November
303°
264°
283°
259°
December
301°
328°
289°
282°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.