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
84.4
89
78
80
95
85
February
79.1
84
73
77
82
79
March
85.9
82
94
73
88
90
April
89.8
89
88
95
95
May
93.2
97
88
91
93
June
92.0
94
89
85
95
July
90.1
80
88
93
95
August
95.4
97
91
92
95
September
94.1
94
88
97
98
October
94.8
97
92
94
96
November
91.8
92
87
98
94
December
88.4
85
94
88
93
Average
89.7
84.7
89.3
86.1
91.3
92.7
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
-1.2
-1
1
0
0
-3
February
-2.1
0
-4
-1
-1
-2
March
1.0
4
2
1
1
0
April
6.2
7
7
10
5
May
10.4
11
12
10
9
June
16.3
17
18
17
18
July
20.3
23
21
19
21
August
21.6
21
23
22
21
September
17.4
20
19
18
17
October
12.1
13
14
13
12
November
5.9
5
6
9
6
December
1.9
3
4
2
5
Average
8.2
0.7
9.9
10.3
10.0
9.1
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
-7.3
-8
-4
-7
-4
-8
February
-9.9
-5
-11
-8
-6
-8
March
-6.9
-2
-4
-5
-6
-7
April
-1.4
0
1
3
-2
May
2.9
3
4
4
3
June
8.6
9
10
10
10
July
13.4
17
13
12
13
August
14.2
14
15
15
14
September
9.9
12
11
12
10
October
5.2
7
7
5
5
November
0.4
0
1
4
0
December
-3.0
-2
-1
-4
-1
Average
1.7
-6.8
3.4
3.5
3.7
2.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
50.6
37
59
69
28
47
February
56.8
51
67
68
59
51
March
35.8
38
25
51
44
31
April
22.8
20
24
17
15
May
17.1
10
17
21
23
June
14.8
16
14
20
11
July
14.2
23
21
17
7
August
11.9
20
15
8
13
September
15.3
16
21
10
8
October
18.4
28
13
14
22
November
32.0
30
50
24
21
December
43.3
42
29
48
29
Average
27.4
42.0
27.8
30.5
23.7
21.1
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
12.1
13
12
13
9
11
February
13.0
12
12
13
13
14
March
12.7
13
12
14
12
12
April
11.7
11
11
14
13
May
10.5
11
10
11
11
June
8.4
9
9
8
8
July
8.5
7
10
9
8
August
9.5
10
9
10
11
September
10.0
9
10
11
11
October
10.2
9
10
9
11
November
13.0
11
14
13
12
December
12.8
12
15
13
11
Average
11.0
12.5
10.1
11.1
10.7
10.7
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
274°
300°
260°
316°
324°
February
273°
285°
261°
305°
260°
March
191°
340°
267°
248°
308°
April
301°
033°
083°
232°
May
293°
281°
273°
272°
June
074°
250°
238°
216°
July
203°
239°
229°
237°
August
207°
249°
251°
244°
September
147°
241°
226°
238°
October
017°
245°
002°
263°
November
265°
288°
212°
249°
December
263°
091°
270°
167°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.