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
75.5
73
82
85
84
February
75.6
80
91
83
67
March
58.9
68
85
3
80
April
67.6
83
0
87
May
62.9
96
0
86
June
68.6
75
0
85
94
July
66.3
58
0
93
93
August
57.2
4
0
91
91
September
63.4
72
0
87
88
October
79.9
85
70
82
November
88.4
92
81
99
88
December
82.7
78
69
85
87
Average
71.2
73.3
73.5
21.2
84.5
89.1
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
2.2
3
3
1
2
February
3.7
7
7
0
1
March
5.2
11
3
0
11
April
12.5
9
6
16
May
20.6
24
21
20
June
23.5
28
24
25
13
July
25.4
31
27
26
17
August
25.7
26
27
27
26
September
21.9
22
22
22
20
October
17.3
17
19
17
November
9.8
10
9
9
13
December
5.4
7
5
8
4
Average
13.4
7.0
15.5
13.2
15.2
15.4
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
-4.6
-3
-1
-5
-3
February
-3.8
-1
-1
0
-5
March
0.1
3
0
0
2
April
5.0
3
2
6
May
11.4
11
12
10
June
14.1
16
16
17
-2
July
14.8
20
19
19
-5
August
18.1
18
19
19
18
September
14.6
15
15
15
13
October
10.0
10
12
9
November
2.8
2
2
2
6
December
-1.0
2
-2
1
-2
Average
5.8
-1.7
7.8
7.4
7.7
5.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
10.4
18
10
11
7
February
7.1
6
6
5
17
March
9.0
13
11
9
7
April
7.6
8
8
5
May
9.3
6
10
8
June
5.6
9
5
4
1
July
4.2
2
6
2
2
August
3.1
1
3
3
4
September
8.7
10
5
8
0
October
6.1
6
6
4
November
7.8
5
15
4
6
December
7.8
6
10
3
12
Average
7.7
12.2
6.5
7.2
6.1
4.0
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
8.5
9
8
8
9
February
8.4
7
9
10
8
March
8.3
8
6
8
9
April
8.5
8
9
9
May
6.3
6
7
7
June
5.5
6
6
6
5
July
4.7
5
5
5
4
August
4.6
5
5
4
5
September
5.0
5
6
6
5
October
6.2
6
6
6
November
7.7
7
9
8
9
December
8.0
8
8
8
9
Average
6.9
8.1
6.5
7.1
6.9
5.9
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
276°
258°
280°
289°
February
254°
245°
245°
273°
March
286°
266°
232°
277°
April
202°
293°
278°
May
263°
161°
285°
June
277°
266°
247°
296°
July
260°
240°
259°
294°
August
267°
242°
220°
267°
September
329°
275°
267°
273°
October
275°
270°
249°
November
268°
254°
278°
251°
December
271°
253°
245°
268°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.