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
76.7
64
76
90
78
74
February
84.5
90
90
89
80
84
March
89.4
85
90
94
96
85
April
90.3
98
97
91
82
May
90.4
96
88
96
90
June
90.7
84
94
96
99
July
94.9
91
93
92
98
August
98.0
97
97
100
100
September
95.2
96
95
98
91
October
91.0
96
92
88
92
November
92.5
96
95
97
93
December
87.3
78
79
92
92
Average
89.4
80.3
91.0
92.5
92.4
90.5
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
1.5
0
4
-2
1
4
February
4.5
9
7
3
-2
3
March
9.1
12
7
10
12
10
April
15.0
17
14
16
14
May
19.9
14
23
20
20
June
26.6
25
28
27
28
July
28.1
28
28
27
30
August
27.7
27
27
29
28
September
24.8
24
24
26
23
October
17.7
18
17
19
16
November
9.6
11
12
9
14
December
5.7
8
4
8
5
Average
14.8
7.0
15.6
15.9
16.1
16.1
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
-5.1
-5
-2
-10
-4
-2
February
-5.7
-1
-3
-6
-12
-4
March
0.7
2
0
0
2
2
April
4.8
5
4
6
5
May
10.5
6
13
11
11
June
15.4
13
14
18
14
July
18.7
17
18
19
19
August
17.7
18
18
19
16
September
15.0
14
14
15
14
October
8.4
9
6
12
6
November
1.4
1
2
0
4
December
-2.6
2
-2
-1
-2
Average
5.9
-2.7
6.6
6.1
7.1
6.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
14.7
14
14
11
14
18
February
12.6
3
10
12
21
18
March
9.6
8
14
16
6
8
April
9.7
5
7
12
12
May
8.6
4
12
5
13
June
5.4
5
4
9
2
July
4.0
5
9
4
3
August
2.0
4
1
1
2
September
4.8
8
7
2
6
October
9.2
10
10
14
7
November
7.3
5
6
4
6
December
7.3
11
11
4
5
Average
7.8
8.1
7.6
8.5
7.5
7.9
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
8.7
8
8
9
7
8
February
9.2
8
10
10
8
10
March
9.8
10
10
9
9
9
April
9.5
10
10
8
9
May
7.9
7
9
8
7
June
6.8
7
6
6
6
July
6.2
6
6
7
6
August
6.5
7
6
6
5
September
6.7
6
6
8
7
October
8.2
9
7
7
8
November
8.7
8
9
9
9
December
8.7
7
7
9
7
Average
8.1
8.9
7.8
7.7
7.6
7.5
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
265°
251°
271°
264°
244°
February
272°
241°
260°
279°
291°
March
290°
300°
265°
299°
273°
April
237°
209°
278°
314°
May
024°
127°
061°
011°
June
004°
311°
270°
068°
July
343°
310°
336°
358°
August
002°
316°
133°
347°
September
061°
314°
280°
302°
October
284°
256°
332°
288°
November
253°
222°
243°
232°
December
249°
192°
234°
242°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.