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
75.6
56
69
90
81
84
February
85.2
93
85
77
91
91
March
87.9
90
81
84
99
87
April
92.9
93
90
96
92
May
93.0
100
93
89
92
June
93.3
84
98
94
99
July
95.3
91
97
92
95
August
94.9
93
91
97
98
September
93.6
89
96
98
92
October
89.1
94
88
82
94
November
89.8
92
85
91
90
December
83.7
69
91
85
88
Average
89.1
79.8
87.0
90.4
91.8
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
1.6
0
3
-1
2
4
February
4.7
8
6
3
0
3
March
9.3
11
7
10
15
11
April
15.5
16
14
18
15
May
22.6
22
24
23
21
June
28.0
26
29
29
30
July
29.9
28
30
29
32
August
28.5
26
30
29
29
September
25.5
24
26
27
24
October
18.2
17
19
21
17
November
9.4
10
11
10
14
December
5.2
7
4
8
5
Average
15.3
6.0
15.9
17.0
17.5
17.0
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
-5.0
-5
-2
-10
-3
-2
February
-5.4
-3
-4
-6
-8
-4
March
-1.4
1
-1
0
1
1
April
4.3
4
4
5
4
May
10.5
8
13
9
11
June
15.8
14
16
19
15
July
18.6
18
19
19
19
August
17.2
15
19
17
17
September
14.3
14
15
15
12
October
8.0
8
6
13
7
November
0.6
-1
-1
1
3
December
-2.5
2
-1
0
-2
Average
5.4
-3.7
6.3
6.2
7.4
6.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
16.9
32
17
13
11
15
February
12.1
3
11
23
12
10
March
11.7
12
21
14
2
7
April
11.8
15
14
11
11
May
8.9
5
11
11
10
June
4.4
7
2
8
1
July
4.0
6
5
8
2
August
3.8
5
6
1
4
September
4.3
3
4
8
3
October
9.6
12
4
11
7
November
9.9
7
9
12
11
December
11.4
19
7
7
11
Average
9.4
15.5
10.3
9.1
8.1
7.1
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
9.3
10
8
10
8
9
February
10.1
9
12
11
9
11
March
10.3
11
10
10
11
9
April
10.1
9
10
10
10
May
8.6
8
9
8
10
June
8.0
7
8
8
8
July
6.8
6
8
7
6
August
6.8
7
7
6
6
September
7.0
6
7
8
8
October
8.6
9
9
8
9
November
8.7
9
5
9
11
December
8.6
7
8
9
9
Average
8.7
9.7
8.0
8.5
8.4
8.6
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
244°
258°
265°
281°
244°
February
249°
240°
251°
275°
271°
March
253°
285°
261°
251°
253°
April
240°
242°
263°
274°
May
358°
170°
259°
292°
June
360°
261°
229°
240°
July
269°
249°
296°
268°
August
288°
256°
233°
284°
September
157°
272°
262°
245°
October
271°
239°
253°
242°
November
251°
222°
234°
240°
December
237°
226°
227°
257°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.