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
83.7
73
71
87
91
87
February
87.4
94
88
89
91
88
March
88.9
86
86
78
100
90
April
91.7
87
90
96
91
97
May
93.5
93
99
96
97
95
June
96.5
94
95
98
98
100
July
97.2
95
96
97
96
100
August
98.3
97
98
100
99
99
September
97.0
100
94
97
96
October
93.0
98
94
85
99
November
92.3
99
86
94
94
December
83.9
73
83
82
89
Average
92.5
90.2
91.6
92.3
93.8
94.7
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
-1.7
0
2
-3
0
2
February
1.5
5
3
0
-2
1
March
5.6
8
4
6
9
7
April
11.8
13
14
11
13
10
May
19.3
21
19
21
20
17
June
24.9
25
24
26
27
26
July
27.6
27
27
28
26
30
August
26.4
26
25
27
28
27
September
22.9
23
23
23
22
October
15.6
17
16
17
14
November
7.7
8
10
8
11
December
2.8
5
2
5
3
Average
14.0
15.5
14.3
14.2
14.5
14.1
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
-7.8
-4
-2
-12
-5
-4
February
-6.3
-3
-5
-8
-8
-6
March
-3.9
0
-2
-2
-2
0
April
3.2
5
5
3
4
2
May
9.7
12
9
11
9
8
June
15.3
16
16
15
17
15
July
18.4
18
18
18
18
20
August
17.4
17
16
18
20
17
September
14.0
15
14
14
13
October
8.0
10
7
11
6
November
0.7
0
2
1
4
December
-3.3
1
-2
-1
-3
Average
6.0
7.7
6.6
5.6
6.4
6.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
24.1
25
35
19
13
18
February
21.2
10
22
27
21
19
March
17.8
19
23
25
7
15
April
16.2
24
14
17
14
9
May
10.8
10
10
9
7
11
June
7.3
12
11
7
5
2
July
6.4
11
9
7
9
3
August
5.1
9
7
9
2
3
September
5.0
2
11
5
2
October
13.5
11
10
18
14
November
14.6
10
18
13
14
December
21.8
29
17
16
24
Average
12.9
14.7
14.3
13.8
10.1
10.2
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
10.2
10
9
10
9
10
February
10.9
10
12
11
10
11
March
11.1
10
12
11
11
11
April
10.7
11
10
11
10
12
May
8.9
8
8
9
9
9
June
9.2
9
8
9
10
9
July
8.2
7
8
9
8
8
August
8.5
8
9
9
8
9
September
8.7
8
8
9
9
October
9.3
10
8
8
9
November
10.1
10
10
10
10
December
9.8
8
10
10
11
Average
9.6
9.1
9.1
9.5
9.2
9.9
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
261°
303°
298°
308°
202°
February
273°
270°
277°
291°
245°
March
280°
314°
280°
288°
140°
April
332°
252°
275°
302°
313°
May
231°
335°
161°
290°
358°
June
251°
022°
281°
239°
262°
July
251°
271°
258°
347°
265°
August
315°
295°
267°
208°
257°
September
116°
298°
284°
239°
October
275°
224°
358°
269°
November
266°
257°
259°
250°
December
293°
282°
253°
277°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.