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
91.7
88
91
98
89
93
February
91.5
98
97
97
77
87
March
92.6
93
93
98
95
82
April
94.4
95
96
99
92
93
May
96.8
97
100
96
94
June
98.3
98
98
99
99
July
99.5
100
100
99
100
August
96.2
100
98
85
100
September
95.8
98
99
100
95
October
94.0
95
98
98
94
November
92.3
94
94
94
92
December
89.8
91
83
97
95
Average
94.3
93.3
95.6
96.8
93.5
93.8
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
14.4
12
16
16
12
16
February
17.0
20
17
15
12
15
March
22.3
23
23
22
23
22
April
26.4
28
27
30
23
26
May
30.8
30
35
28
33
June
34.7
36
36
33
36
July
35.4
38
38
32
37
August
34.5
38
34
33
37
September
30.5
34
32
32
29
October
25.4
26
26
29
27
November
19.3
19
17
21
22
December
16.3
16
17
23
16
Average
24.9
20.6
26.5
26.7
25.1
26.3
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
0.4
-1
2
-1
1
2
February
2.0
5
2
-2
-2
1
March
7.7
8
7
5
7
10
April
11.5
12
11
14
10
11
May
16.4
17
19
16
16
June
20.7
21
23
21
21
July
22.2
24
25
21
24
August
22.1
25
23
21
23
September
18.2
22
19
19
16
October
11.7
13
12
13
11
November
5.7
8
5
6
8
December
2.5
3
6
5
0
Average
11.0
6.1
12.8
12.6
11.5
12.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
1.1
2
1
1
4
2
February
2.5
1
3
3
5
9
March
1.1
1
1
0
1
7
April
0.8
0
1
0
5
1
May
0.5
2
0
2
0
June
0.3
1
0
2
0
July
0.2
0
0
2
0
August
0.4
0
2
1
1
September
0.8
2
1
0
2
October
1.0
2
4
0
1
November
1.0
3
2
1
1
December
1.1
0
1
1
6
Average
0.9
0.7
1.2
1.1
1.7
2.2
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
9.9
10
12
10
10
10
February
11.0
12
13
10
11
11
March
11.8
11
13
13
15
11
April
12.3
12
12
14
12
12
May
11.5
9
13
12
12
June
10.4
9
12
9
12
July
9.1
10
10
8
10
August
9.0
10
9
10
10
September
7.3
8
9
2
8
October
8.8
10
10
6
11
November
10.0
10
12
10
11
December
9.7
10
11
10
11
Average
10.2
11.1
10.5
10.9
9.6
10.6
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
230°
228°
253°
318°
219°
February
233°
218°
153°
097°
216°
March
212°
203°
228°
182°
196°
April
214°
207°
191°
131°
209°
May
148°
188°
128°
160°
June
169°
158°
148°
165°
July
156°
159°
143°
159°
August
151°
129°
165°
163°
September
156°
160°
163°
094°
October
146°
167°
201°
149°
November
196°
194°
180°
180°
December
213°
206°
225°
245°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.