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
82.4
82
75
70
93
85
February
84.9
85
82
73
87
88
March
91.6
91
91
96
91
95
April
94.3
99
97
90
92
May
92.9
93
95
95
96
June
91.4
91
90
94
91
July
86.9
88
82
94
83
August
86.0
86
86
90
81
September
86.9
84
78
84
95
October
86.8
83
70
98
93
November
86.6
82
90
91
90
December
89.4
93
87
87
86
Average
88.4
86.1
87.8
85.0
91.2
89.7
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
4.6
5
6
4
5
2
February
4.1
6
4
6
3
5
March
6.7
8
6
7
5
7
April
10.1
9
10
11
10
May
14.7
16
14
13
16
June
16.8
18
18
17
16
July
19.0
20
19
19
17
August
18.9
20
20
18
16
September
15.8
15
17
14
16
October
10.9
12
12
10
10
November
7.1
8
5
8
6
December
4.3
7
1
0
7
Average
10.5
6.0
11.8
11.3
10.1
10.5
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
0.5
0
2
-1
2
-2
February
-1.5
1
0
2
-1
1
March
0.6
1
0
2
1
0
April
3.2
3
2
2
3
May
7.4
8
5
7
8
June
10.2
10
10
11
10
July
12.7
14
13
13
12
August
12.8
13
14
12
12
September
10.1
10
11
10
11
October
6.0
7
8
5
4
November
3.1
5
1
3
2
December
0.4
3
-4
-5
3
Average
5.0
0.6
6.3
5.5
4.9
5.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
38.0
42
48
35
35
35
February
27.8
15
47
38
32
34
March
27.8
25
24
32
36
31
April
25.9
31
17
23
25
May
20.4
15
28
19
15
June
22.6
20
17
19
27
July
20.1
16
28
16
22
August
21.3
14
17
19
40
September
28.2
35
30
46
24
October
30.0
34
31
35
24
November
37.6
43
24
48
39
December
32.5
53
18
21
38
Average
26.9
26.8
29.0
25.7
28.5
28.4
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
7.8
7
8
8
9
8
February
7.3
7
8
8
7
7
March
8.0
8
8
9
8
8
April
8.6
9
8
8
10
May
8.0
8
8
8
8
June
7.6
8
7
8
8
July
7.4
7
8
7
8
August
7.9
8
8
7
8
September
7.6
8
8
8
8
October
7.5
8
8
9
5
November
7.6
8
7
8
9
December
7.7
9
6
5
10
Average
7.7
7.2
8.0
7.6
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
142°
137°
136°
142°
146°
February
309°
135°
136°
139°
137°
March
121°
070°
131°
132°
024°
April
132°
098°
060°
110°
May
045°
119°
118°
122°
June
117°
109°
103°
122°
July
079°
123°
100°
118°
August
092°
073°
094°
130°
September
130°
114°
131°
093°
October
134°
128°
135°
131°
November
135°
134°
140°
141°
December
141°
173°
266°
140°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.