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
72.0
67
20
96
79
72
February
80.4
91
17
97
85
94
March
74.7
95
0
94
86
64
April
79.5
93
0
92
93
96
May
87.0
68
91
93
89
June
95.5
98
93
95
99
July
96.0
96
96
94
97
August
94.4
97
92
98
98
September
93.9
92
97
98
88
October
84.8
92
59
89
92
November
89.5
98
65
99
94
December
86.1
79
74
92
87
Average
86.3
86.9
64.5
88.2
91.9
89.4
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
-1.3
-4
1
1
1
-1
February
1.9
10
1
4
-6
3
March
8.3
12
0
10
13
10
April
13.9
18
0
16
17
16
May
21.2
19
22
21
20
June
28.9
29
29
30
30
July
29.0
29
30
29
30
August
27.7
29
29
29
29
September
25.6
26
26
27
24
October
15.9
17
15
18
14
November
8.4
12
4
11
12
December
3.2
6
1
6
3
Average
14.5
8.9
14.0
15.9
16.4
15.8
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
-9.5
-11
-2
-13
-7
-9
February
-9.9
-4
-1
-11
-14
-7
March
-2.9
-1
0
-2
1
0
April
2.7
4
0
2
4
2
May
10.1
8
11
10
10
June
16.8
16
17
17
19
July
17.3
14
19
17
18
August
16.2
16
17
17
17
September
13.3
12
13
13
11
October
4.5
6
2
8
3
November
-3.6
-2
-5
-1
0
December
-6.0
-3
-7
-5
-8
Average
3.7
-3.3
5.3
3.9
5.1
4.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
7.1
13
4
3
8
9
February
6.3
2
0
4
13
4
March
4.7
4
0
4
4
5
April
3.2
4
0
5
2
3
May
3.0
1
5
2
5
June
1.9
2
3
2
1
July
1.4
2
0
1
1
August
1.7
2
2
0
1
September
2.1
2
1
1
4
October
3.4
1
0
4
3
November
2.9
2
7
1
3
December
6.2
7
14
1
8
Average
3.7
5.3
1.7
3.5
2.9
3.6
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
8.3
8
2
10
9
9
February
8.7
10
2
11
8
10
March
9.3
11
0
12
12
8
April
10.1
13
0
14
11
10
May
8.7
6
11
9
9
June
7.8
7
8
7
9
July
6.3
6
8
7
7
August
6.6
7
6
8
8
September
7.9
8
8
8
9
October
8.8
10
6
8
10
November
9.4
10
8
10
10
December
9.0
8
11
10
8
Average
8.6
10.8
5.4
9.4
8.9
8.8
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
287°
277°
258°
326°
271°
February
249°
276°
310°
325°
300°
March
360°
360°
338°
161°
275°
April
279°
360°
251°
294°
294°
May
155°
190°
171°
004°
June
144°
210°
204°
171°
July
267°
214°
171°
178°
August
189°
179°
171°
190°
September
185°
183°
183°
227°
October
289°
273°
217°
275°
November
219°
287°
251°
229°
December
271°
207°
229°
282°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.