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
78.0
74
67
79
84
88
February
79.4
90
81
76
76
79
March
79.7
74
85
74
85
75
April
80.7
87
81
91
89
71
May
77.6
96
73
88
87
June
76.5
79
86
79
81
July
84.3
81
91
77
84
August
84.7
80
85
82
90
September
83.0
84
91
92
81
October
80.9
86
70
85
83
November
87.8
90
90
98
81
December
83.4
74
88
93
80
Average
81.5
81.4
82.3
82.7
85.2
81.8
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
4.0
4
7
3
3
4
February
5.4
5
6
7
3
5
March
7.5
9
8
10
8
8
April
12.2
12
15
14
12
9
May
17.3
19
18
17
17
June
22.5
22
23
24
22
July
26.5
27
28
24
26
August
26.1
24
27
27
26
September
22.1
22
22
23
22
October
17.2
17
17
19
16
November
11.0
10
13
10
13
December
6.1
8
8
7
6
Average
14.0
7.5
15.4
16.1
14.7
14.6
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
-4.5
-3
0
-7
-2
-1
February
-3.0
-2
-3
-5
-3
-1
March
-1.5
2
0
0
0
2
April
3.8
4
6
4
5
4
May
8.1
8
10
10
9
June
12.5
13
13
16
15
July
18.0
19
19
18
20
August
18.1
18
20
20
20
September
14.5
15
14
16
14
October
9.7
11
9
12
9
November
2.4
1
4
2
5
December
-1.1
1
0
0
1
Average
5.8
0.0
7.4
7.0
7.8
8.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
13.5
17
19
20
11
1
February
9.1
9
7
14
15
6
March
8.4
13
11
8
4
8
April
7.2
9
3
3
4
26
May
3.4
1
3
4
6
June
3.9
7
3
3
3
July
1.4
1
1
4
2
August
3.0
4
2
8
5
September
5.6
10
3
7
1
October
8.9
8
11
7
14
November
5.8
5
5
4
6
December
12.3
10
21
7
16
Average
6.9
11.6
6.5
6.3
5.8
7.2
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
9.8
12
10
12
13
10
February
9.2
11
12
11
9
12
March
10.5
13
11
11
13
13
April
9.7
11
11
12
11
14
May
8.6
10
12
11
11
June
8.1
8
10
11
9
July
8.7
9
11
8
9
August
9.1
9
10
9
11
September
9.3
9
9
9
10
October
9.9
8
10
10
10
November
10.3
9
11
10
10
December
9.7
9
13
8
11
Average
9.7
11.7
9.5
10.8
10.0
10.6
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
269°
300°
290°
272°
291°
February
293°
288°
248°
302°
253°
March
325°
305°
254°
257°
055°
April
187°
199°
247°
320°
312°
May
231°
109°
253°
255°
June
204°
218°
229°
243°
July
213°
228°
248°
223°
August
220°
224°
223°
231°
September
046°
296°
242°
251°
October
266°
039°
077°
136°
November
272°
254°
295°
247°
December
269°
325°
284°
254°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.