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
85.8
84
70
95
89
96
February
89.5
82
81
98
99
98
March
89.8
89
82
89
86
90
April
98.4
97
100
99
98
May
98.1
100
100
100
100
June
99.8
100
100
100
100
July
98.9
100
98
99
100
August
99.1
99
97
100
99
September
98.1
98
95
97
100
October
98.2
100
99
98
100
November
95.8
96
90
100
99
December
91.2
96
84
84
96
Average
94.3
85.3
93.4
95.7
95.9
98.0
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
6.2
6
2
7
7
7
February
7.6
8
5
8
9
10
March
11.2
11
7
12
11
11
April
17.8
17
18
18
17
May
21.5
22
23
23
24
June
28.3
26
29
30
28
July
30.2
33
29
30
30
August
28.8
29
27
29
32
September
25.4
25
25
26
27
October
18.6
20
17
17
23
November
13.0
13
9
15
13
December
7.6
10
4
7
8
Average
16.9
8.2
17.5
17.9
18.3
19.1
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
-9.6
-8
-11
-8
-10
-8
February
-8.1
-5
-11
-10
-8
-8
March
-5.8
-3
-3
-6
-6
-4
April
-3.7
-3
-4
-2
-2
May
0.6
2
1
-1
1
June
5.3
3
7
7
4
July
10.9
10
12
13
9
August
10.1
12
12
10
9
September
5.9
6
8
7
4
October
-1.2
0
0
-1
-2
November
-6.4
-4
-8
-5
-5
December
-9.9
-6
-10
-6
-11
Average
-1.0
-6.4
-1.6
-1.8
-1.8
-2.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.2
13
19
4
7
2
February
10.5
16
19
4
3
4
March
8.9
9
17
13
10
8
April
1.6
3
1
2
1
May
2.0
2
0
0
1
June
0.4
1
1
1
0
July
2.6
2
5
1
2
August
1.5
4
3
1
1
September
2.2
6
6
1
0
October
2.4
2
4
3
0
November
3.9
3
10
0
2
December
5.3
1
12
10
5
Average
5.0
12.5
6.3
4.8
3.1
1.9
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
7.1
6
8
7
7
7
February
8.5
8
10
9
7
7
March
9.1
10
11
8
9
9
April
9.4
9
10
10
9
May
9.0
9
11
9
9
June
8.8
9
9
8
10
July
6.3
7
6
5
7
August
6.2
6
4
7
7
September
7.6
7
6
7
7
October
7.9
8
7
9
7
November
7.9
8
9
7
8
December
6.8
6
7
8
7
Average
7.9
8.2
8.2
7.8
7.7
8.0
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
247°
211°
047°
108°
237°
February
222°
202°
072°
253°
289°
March
220°
219°
228°
216°
206°
April
235°
225°
230°
226°
May
209°
225°
223°
217°
June
219°
215°
227°
217°
July
230°
218°
260°
222°
August
224°
215°
221°
227°
September
212°
194°
208°
286°
October
195°
056°
202°
250°
November
189°
212°
112°
200°
December
062°
218°
213°
043°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.