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
91.1
89
90
94
97
88
February
94.0
86
93
98
97
93
March
98.4
99
100
96
100
100
April
99.5
100
100
99
100
100
May
99.7
100
100
98
100
100
June
99.9
100
100
100
100
100
July
98.8
100
100
100
92
100
August
93.5
100
84
100
87
100
September
97.2
100
100
100
88
October
99.4
100
100
99
99
November
97.5
99
92
98
98
December
94.3
90
97
96
91
Average
97.2
97.2
96.5
98.0
97.0
96.7
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
2.0
1
4
0
4
3
February
3.5
7
4
5
3
6
March
10.0
11
10
11
12
10
April
15.3
16
15
14
18
16
May
22.5
21
25
19
22
21
June
25.7
24
28
24
30
23
July
31.2
33
32
31
34
29
August
29.8
30
30
32
30
30
September
23.1
24
25
23
25
October
14.6
15
18
14
14
November
6.4
7
2
8
7
December
2.0
5
-3
0
4
Average
15.9
17.9
16.5
15.5
16.5
15.6
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
-3.6
-4
-1
-3
-1
-1
February
-4.4
-1
-2
-3
-3
-1
March
-1.3
0
-2
2
0
-1
April
2.6
3
2
1
3
2
May
7.9
6
11
6
7
8
June
11.1
10
12
11
13
10
July
14.6
16
15
14
17
14
August
14.1
15
15
15
15
14
September
10.0
11
10
10
11
October
4.2
4
6
5
5
November
0.6
1
-3
2
2
December
-3.6
1
-6
-6
-2
Average
4.8
5.6
5.6
4.6
5.0
4.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
20.9
28
19
14
24
32
February
15.1
22
12
7
15
11
March
9.5
12
10
7
2
7
April
9.7
8
9
12
6
3
May
8.0
8
11
11
4
13
June
7.1
8
5
15
5
12
July
2.1
3
1
2
1
5
August
2.3
5
4
1
3
2
September
6.1
9
3
5
3
October
5.7
3
1
14
7
November
12.5
6
21
15
9
December
20.5
19
31
32
17
Average
9.3
10.8
8.5
9.3
9.2
9.3
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
9.0
9
8
11
9
10
February
8.6
6
9
10
10
7
March
8.0
8
7
8
9
9
April
7.4
8
8
7
7
8
May
6.2
6
7
6
7
6
June
6.2
7
6
6
6
6
July
6.3
6
6
6
7
6
August
6.4
7
7
6
6
6
September
6.5
7
6
7
7
October
8.3
7
8
9
8
November
9.5
9
9
11
11
December
9.5
10
11
9
8
Average
7.4
6.9
7.4
7.6
7.8
7.6
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
173°
168°
169°
170°
176°
February
014°
165°
167°
168°
166°
March
174°
170°
168°
172°
292°
April
349°
168°
185°
011°
002°
May
338°
358°
216°
352°
358°
June
347°
358°
354°
359°
345°
July
356°
355°
359°
360°
357°
August
358°
356°
359°
002°
004°
September
354°
008°
170°
339°
October
329°
190°
171°
168°
November
169°
160°
173°
171°
December
171°
001°
195°
171°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.