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
90.3
75
94
94
94
88
February
86.6
95
85
91
80
95
March
94.0
96
94
98
97
83
April
93.8
95
99
92
98
May
94.0
93
92
94
94
June
97.1
95
96
96
100
July
98.4
98
100
98
98
August
93.1
100
97
99
100
September
93.8
97
96
100
90
October
92.2
93
100
97
88
November
80.5
87
85
95
94
December
85.0
91
74
98
92
Average
91.6
88.3
93.5
94.4
95.2
93.4
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
11.5
8
14
12
11
13
February
13.2
17
15
13
6
13
March
19.5
20
18
20
20
20
April
23.5
24
26
22
23
May
28.6
28
31
26
29
June
33.4
32
34
32
35
July
36.2
36
39
33
36
August
34.7
38
36
35
35
September
31.4
34
33
34
28
October
23.9
25
25
26
23
November
15.5
18
15
19
20
December
12.8
14
12
20
14
Average
22.6
14.9
24.2
25.2
23.7
24.1
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
-2.3
-3
0
-5
0
1
February
-1.7
4
0
-4
-6
0
March
5.3
6
4
3
6
8
April
8.9
8
10
8
9
May
14.2
10
16
14
15
June
20.4
20
21
20
21
July
21.7
16
25
22
24
August
19.6
23
23
22
21
September
17.8
18
19
19
16
October
10.6
12
11
12
9
November
4.2
5
5
5
7
December
0.6
2
2
3
-1
Average
9.1
2.0
9.3
10.8
10.4
10.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
3.7
7
5
2
2
5
February
4.9
7
5
8
7
4
March
3.1
4
2
4
1
8
April
3.7
8
1
2
0
May
3.5
5
9
4
3
June
2.1
3
1
5
0
July
1.4
4
1
2
3
August
2.3
1
5
2
0
September
3.7
2
2
2
4
October
6.8
9
7
2
8
November
3.1
4
7
5
4
December
3.2
3
7
1
6
Average
3.7
5.9
4.2
4.2
2.8
3.6
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
11.5
10
12
10
11
12
February
12.1
12
14
12
9
13
March
12.7
13
13
15
11
11
April
14.1
14
17
14
14
May
12.1
11
14
12
12
June
12.0
11
13
10
14
July
10.1
11
13
9
10
August
9.4
10
11
11
9
September
10.6
11
12
11
9
October
11.8
12
11
12
11
November
10.1
11
13
12
11
December
10.3
11
11
12
10
Average
11.5
11.6
11.6
12.8
11.0
11.3
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
050°
234°
356°
339°
113°
February
225°
216°
247°
042°
337°
March
190°
169°
253°
200°
122°
April
162°
177°
187°
169°
May
158°
171°
140°
125°
June
133°
170°
175°
187°
July
186°
183°
174°
163°
August
163°
175°
182°
161°
September
165°
184°
182°
132°
October
184°
185°
173°
144°
November
200°
158°
196°
186°
December
248°
195°
215°
338°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.