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
66.9
52
47
86
69
73
February
84.0
94
79
91
82
91
March
85.6
89
84
79
88
76
April
89.1
88
87
95
90
May
88.0
94
87
86
87
June
91.5
83
92
93
96
July
94.7
96
91
91
97
August
91.9
92
86
95
98
September
88.4
83
91
95
86
October
87.4
81
97
83
92
November
86.4
90
81
99
88
December
77.5
64
70
83
82
Average
85.7
77.8
82.5
87.2
88.7
88.5
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
-3.6
-3
0
-5
-2
0
February
0.7
9
2
-1
-7
0
March
7.4
11
6
7
10
8
April
13.8
16
12
15
14
May
21.1
23
22
20
19
June
27.0
28
27
28
27
July
27.9
28
28
28
29
August
26.4
27
27
28
28
September
23.6
24
23
25
21
October
15.5
16
17
18
14
November
7.1
9
9
8
12
December
2.6
5
2
4
1
Average
13.1
5.5
15.4
14.4
14.7
14.3
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
-10.6
-8
-6
-15
-8
-7
February
-9.3
-3
-8
-11
-15
-9
March
-2.5
0
-2
-2
0
0
April
2.9
3
2
5
2
May
10.4
11
12
10
9
June
15.6
15
16
18
13
July
17.6
17
18
18
19
August
16.5
17
18
18
16
September
13.2
15
13
13
11
October
5.7
7
4
10
3
November
-2.3
-1
0
-1
1
December
-6.9
-1
-5
-4
-7
Average
3.6
-4.3
5.6
4.5
5.3
4.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.5
19
15
10
5
5
February
7.6
0
19
6
7
5
March
8.6
11
11
14
7
9
April
8.5
9
17
5
4
May
6.3
4
10
7
8
June
4.9
4
6
6
7
July
2.0
3
5
1
1
August
3.1
4
5
5
1
September
4.6
3
1
3
12
October
7.5
10
2
11
8
November
8.4
5
20
13
7
December
8.5
17
16
4
6
Average
6.8
10.6
8.1
8.8
5.9
6.0
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
9
9
12
9
10
February
10.7
11
11
12
9
10
March
11.2
12
11
11
12
11
April
12.0
13
14
11
12
May
9.6
9
11
10
10
June
8.4
7
9
8
8
July
7.3
7
8
7
7
August
7.1
7
7
7
8
September
8.3
8
9
8
10
October
10.1
10
10
9
10
November
10.6
10
12
12
12
December
9.8
10
11
11
9
Average
9.6
10.7
9.2
10.3
9.2
9.5
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
284°
267°
270°
334°
258°
February
246°
268°
272°
299°
291°
March
308°
294°
314°
179°
240°
April
254°
243°
259°
288°
May
079°
140°
179°
042°
June
058°
228°
227°
183°
July
290°
234°
295°
196°
August
244°
228°
199°
209°
September
148°
281°
240°
237°
October
280°
242°
005°
281°
November
247°
237°
254°
221°
December
209°
194°
230°
268°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.