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
73.7
68
69
77
79
79
February
84.3
91
92
82
77
77
March
85.2
85
81
90
94
81
April
89.5
95
93
92
85
May
90.6
96
92
91
91
June
93.3
83
98
100
98
July
96.9
95
99
91
99
August
97.3
95
98
97
99
September
95.3
99
91
95
95
October
91.2
94
98
91
86
November
90.8
96
91
95
92
December
84.7
81
89
86
84
Average
89.1
82.0
90.1
92.1
91.2
89.5
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
2.5
2
5
-1
1
5
February
5.6
7
8
4
0
3
March
8.7
11
7
11
12
10
April
14.8
16
13
15
12
May
20.7
20
22
19
19
June
25.8
24
26
26
27
July
27.7
26
29
26
29
August
27.1
24
26
30
26
September
24.3
23
22
24
26
October
17.9
17
16
22
15
November
9.8
10
13
9
13
December
5.5
8
4
8
4
Average
14.8
6.8
15.6
15.9
16.2
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
-5.9
-3
-1
-9
-3
-2
February
-4.7
-2
-3
-6
-7
-3
March
-1.8
2
-1
0
1
2
April
4.7
5
4
6
2
May
10.9
8
12
9
10
June
16.3
13
16
18
16
July
18.9
18
18
19
19
August
18.1
17
18
19
18
September
15.2
14
14
15
14
October
9.5
10
7
12
8
November
2.2
2
3
2
5
December
-1.5
3
-1
1
-1
Average
6.3
-2.7
7.0
6.5
7.7
7.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
28.2
34
30
32
17
27
February
18.8
7
15
30
26
19
March
14.7
13
23
13
7
12
April
10.3
9
12
9
12
May
9.3
8
11
10
14
June
4.1
3
3
6
2
July
3.3
5
3
6
2
August
3.1
4
4
2
5
September
3.6
3
7
4
3
October
8.6
9
7
9
12
November
13.6
12
14
14
15
December
18.0
20
8
12
19
Average
11.3
17.0
10.7
11.0
9.5
11.0
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
9.5
10
8
9
8
9
February
10.2
9
10
10
9
9
March
9.9
9
9
10
10
8
April
9.2
9
9
9
9
May
8.2
7
8
8
8
June
7.7
7
7
7
7
July
7.0
6
8
7
6
August
7.0
7
6
6
7
September
7.6
6
7
8
8
October
8.5
8
9
7
8
November
9.8
9
9
10
10
December
9.2
8
8
9
9
Average
8.6
9.3
7.7
8.3
8.0
8.1
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
240°
249°
253°
265°
234°
February
264°
247°
235°
270°
267°
March
251°
272°
243°
262°
252°
April
275°
265°
275°
290°
May
359°
179°
322°
270°
June
315°
281°
246°
304°
July
283°
276°
296°
303°
August
304°
287°
288°
291°
September
356°
280°
254°
218°
October
250°
237°
231°
242°
November
241°
231°
243°
242°
December
224°
217°
226°
244°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.