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
89.0
86
87
74
94
91
February
87.8
92
92
84
83
90
March
96.0
92
97
94
98
100
April
97.3
95
99
98
99
May
95.6
94
96
94
97
June
95.0
90
93
97
96
July
95.2
95
92
93
93
August
93.0
97
95
97
95
September
90.2
88
91
96
73
October
86.2
84
75
95
82
November
92.7
95
91
93
95
December
87.8
80
80
90
89
Average
92.2
89.7
91.2
89.3
94.3
91.8
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
8.2
8
9
8
9
9
February
7.7
10
8
9
7
9
March
11.8
13
12
12
12
10
April
14.6
14
14
16
15
May
19.2
21
16
18
19
June
22.0
22
22
24
20
July
25.2
26
26
26
23
August
25.9
27
28
25
25
September
22.1
22
24
21
23
October
15.6
17
19
14
15
November
10.3
11
8
11
10
December
7.4
10
4
5
9
Average
15.2
10.2
16.7
16.0
15.6
15.7
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
1.6
1
2
1
3
4
February
0.6
3
1
1
1
1
March
2.1
3
1
4
2
2
April
4.7
5
4
4
5
May
8.1
9
7
7
9
June
10.7
10
11
12
11
July
11.7
11
13
12
12
August
12.2
13
13
13
11
September
10.2
10
10
10
11
October
5.9
6
7
7
8
November
2.8
2
-1
5
4
December
1.1
4
-2
-1
2
Average
5.5
2.1
6.1
5.8
6.2
6.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
22.8
35
26
17
25
28
February
23.1
24
34
13
37
22
March
15.2
23
19
18
15
17
April
15.2
25
14
9
9
May
9.2
6
23
8
15
June
9.4
12
11
8
14
July
2.4
1
3
0
8
August
3.8
5
3
5
4
September
7.8
9
1
10
6
October
13.6
14
13
16
12
November
21.2
10
21
34
18
December
21.9
33
16
23
20
Average
14.4
27.3
15.1
12.5
14.5
13.7
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
5.5
4
4
5
5
8
February
5.1
5
6
5
5
5
March
6.2
6
6
6
6
7
April
6.7
7
7
6
5
May
5.1
5
6
6
5
June
5.2
5
5
5
5
July
5.0
6
4
5
5
August
4.8
5
5
5
5
September
5.1
5
5
6
5
October
5.1
5
5
7
5
November
5.5
4
4
7
7
December
4.5
4
4
6
5
Average
5.3
5.4
5.1
5.0
5.6
5.5
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
140°
122°
151°
138°
146°
February
157°
158°
167°
178°
175°
March
155°
168°
175°
172°
170°
April
162°
174°
260°
245°
May
293°
179°
240°
257°
June
277°
218°
276°
251°
July
296°
299°
304°
300°
August
296°
267°
280°
286°
September
252°
284°
180°
290°
October
193°
186°
146°
201°
November
164°
264°
153°
147°
December
145°
092°
160°
142°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.