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
94.7
93
99
96
92
95
February
92.0
94
96
92
87
90
March
93.9
91
96
95
97
94
April
96.0
97
97
95
98
95
May
94.2
97
93
95
97
June
94.6
93
97
95
94
July
93.5
97
95
97
80
August
90.6
98
95
96
71
September
90.8
91
91
94
91
October
93.6
97
93
89
92
November
95.1
98
93
98
97
December
91.9
93
92
98
92
Average
93.5
93.8
96.0
93.9
94.8
90.1
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
7.1
7
10
5
6
9
February
11.2
12
13
11
6
11
March
14.2
16
14
16
16
17
April
20.1
22
22
19
20
17
May
23.9
23
25
23
21
June
28.0
27
28
29
28
July
30.8
32
30
31
32
August
29.6
31
30
31
29
September
26.0
27
26
26
24
October
21.0
22
19
22
21
November
13.7
15
15
13
17
December
9.4
11
8
14
8
Average
18.9
13.9
20.5
19.6
19.7
19.6
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
-3.8
-3
-1
-5
-2
0
February
0.0
-2
0
-1
-1
1
March
2.0
2
0
3
3
5
April
6.6
8
5
6
6
6
May
11.6
8
12
10
11
June
15.8
12
17
17
17
July
18.3
17
18
19
20
August
17.6
16
18
19
18
September
14.0
12
13
14
12
October
8.7
7
5
12
8
November
1.8
-1
4
1
5
December
-1.5
-1
0
2
-1
Average
7.1
1.2
6.2
7.7
8.2
8.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
8.2
14
9
9
7
9
February
11.0
10
8
12
14
11
March
7.5
6
10
7
5
6
April
7.7
4
7
9
5
9
May
8.1
5
8
6
7
June
5.0
6
5
4
5
July
4.1
2
7
3
3
August
5.2
4
5
4
8
September
7.2
7
8
8
4
October
6.7
4
8
7
7
November
6.1
6
8
3
6
December
8.7
8
5
1
11
Average
7.1
8.0
6.1
7.5
5.4
6.8
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
4.9
5
5
5
3
4
February
5.4
4
6
6
5
5
March
5.8
5
6
7
5
5
April
5.4
5
5
5
5
6
May
4.4
4
4
4
5
June
4.1
5
4
4
4
July
3.2
4
3
3
3
August
3.0
4
3
3
2
September
3.6
3
4
4
3
October
4.0
4
5
4
4
November
4.4
4
5
4
5
December
3.7
3
4
4
5
Average
4.4
4.7
4.3
4.5
4.0
4.2
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
257°
245°
251°
280°
257°
February
241°
243°
236°
269°
242°
March
270°
259°
236°
259°
233°
April
241°
219°
250°
260°
274°
May
356°
360°
303°
275°
June
300°
246°
220°
284°
July
218°
217°
236°
253°
August
235°
225°
198°
261°
September
004°
288°
239°
175°
October
247°
230°
257°
250°
November
260°
245°
254°
239°
December
246°
228°
221°
246°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.