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
72.4
66
65
79
74
74
February
81.0
92
89
85
78
76
March
83.3
78
81
85
94
82
April
89.1
91
89
93
90
May
90.6
93
90
89
91
June
91.6
81
95
96
96
July
94.5
91
95
90
96
August
93.6
92
93
94
95
September
92.4
95
90
93
94
October
87.6
86
95
84
81
November
85.8
90
83
93
90
December
77.2
78
66
83
75
Average
86.3
78.2
86.4
88.3
89.0
87.5
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
1
6
0
2
5
February
6.2
8
11
5
0
4
March
10.1
11
9
12
15
12
April
16.1
17
15
17
14
May
22.1
21
23
21
21
June
26.4
24
28
27
27
July
29.1
28
30
28
31
August
27.9
26
28
29
28
September
24.9
23
24
26
24
October
18.3
16
18
21
17
November
9.8
10
12
10
13
December
5.7
7
5
9
5
Average
15.5
6.8
16.5
17.0
17.1
16.7
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
-4.0
-4
1
-8
-3
-1
February
-3.1
-2
-1
-5
-6
-3
March
0.3
2
0
1
1
3
April
5.4
6
5
6
4
May
11.6
9
14
10
10
June
16.3
13
17
18
17
July
19.1
18
20
19
20
August
17.9
16
19
20
18
September
14.9
13
15
15
14
October
9.2
8
7
13
9
November
1.7
1
4
1
4
December
-1.0
1
0
1
-2
Average
6.3
-2.4
7.0
7.6
8.0
7.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
31.3
35
34
28
28
30
February
21.4
10
15
25
27
23
March
19.6
19
24
23
9
14
April
13.0
14
15
9
14
May
9.3
10
7
10
11
June
4.4
7
2
4
4
July
3.4
3
4
6
2
August
3.3
6
3
4
3
September
5.1
3
8
5
2
October
8.8
9
4
8
12
November
13.9
7
15
12
15
December
20.3
21
18
11
24
Average
13.2
21.5
12.2
11.6
10.2
11.9
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
9.4
10
9
10
8
9
February
10.1
9
11
11
9
10
March
10.3
10
11
11
10
9
April
9.6
9
10
9
9
May
8.2
7
9
7
9
June
8.0
8
8
8
7
July
7.0
7
8
7
7
August
6.9
7
7
6
7
September
7.3
6
7
9
8
October
8.5
8
9
8
8
November
9.4
10
10
9
10
December
8.9
8
8
9
9
Average
8.7
9.8
8.3
8.9
8.3
8.4
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
232°
235°
253°
260°
240°
February
250°
234°
239°
280°
260°
March
249°
261°
245°
248°
240°
April
239°
243°
264°
281°
May
355°
173°
301°
242°
June
315°
266°
227°
255°
July
253°
255°
279°
271°
August
277°
242°
253°
249°
September
007°
265°
235°
210°
October
251°
228°
214°
240°
November
234°
231°
236°
239°
December
223°
217°
221°
237°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.