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
82.7
71
73
82
88
92
February
82.0
89
81
81
79
81
March
86.4
87
86
75
90
87
April
87.4
80
95
95
91
May
90.2
96
89
95
92
June
91.9
86
93
96
94
July
89.0
80
94
83
94
August
91.5
87
94
92
95
September
90.0
82
90
95
92
October
85.4
81
83
84
82
November
90.7
90
86
95
90
December
81.6
69
75
80
88
Average
87.3
82.7
83.0
87.2
89.7
90.2
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
2.3
2
5
1
2
4
February
4.7
6
6
5
1
5
March
8.6
11
8
10
11
11
April
15.0
18
15
16
13
May
21.6
22
23
22
21
June
26.4
25
27
28
28
July
29.4
30
30
27
31
August
28.2
26
30
29
29
September
23.9
24
23
24
24
October
17.8
19
17
19
17
November
9.9
9
13
10
13
December
4.6
7
5
7
5
Average
14.9
6.3
16.6
16.8
16.3
16.7
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
-6.0
-4
-2
-9
-6
-5
February
-6.9
-4
-6
-6
-6
-4
March
-2.3
1
-1
-2
-2
0
April
3.5
5
3
4
2
May
8.9
7
11
9
8
June
13.8
14
14
16
14
July
17.4
18
17
17
19
August
16.8
16
18
19
16
September
12.8
13
12
14
12
October
7.2
8
6
9
7
November
-1.4
-2
1
-1
1
December
-4.6
0
-3
-2
-3
Average
4.4
-3.8
5.8
5.4
5.8
5.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
13.6
22
24
14
8
7
February
12.8
7
13
17
22
10
March
10.6
14
16
9
6
8
April
14.1
13
14
12
16
May
8.2
6
7
9
4
June
6.1
6
7
5
5
July
7.3
10
4
14
3
August
6.0
9
4
9
6
September
9.6
19
13
9
4
October
11.9
13
10
10
16
November
9.7
9
12
6
10
December
14.1
18
22
7
12
Average
10.4
14.1
12.2
9.9
9.5
8.0
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
7.2
6
6
8
7
7
February
7.7
8
8
8
7
7
March
8.7
9
8
8
9
8
April
8.3
7
9
8
10
May
7.0
7
7
7
9
June
6.3
6
6
6
6
July
5.4
5
7
5
6
August
6.0
6
7
5
6
September
5.7
5
5
6
6
October
6.2
5
6
6
6
November
7.1
7
7
6
7
December
6.6
5
8
6
8
Average
6.9
7.5
6.1
7.0
6.7
7.0
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
315°
319°
309°
320°
297°
February
301°
301°
282°
326°
287°
March
321°
315°
301°
294°
317°
April
301°
299°
315°
306°
May
300°
131°
304°
285°
June
315°
266°
214°
252°
July
206°
240°
321°
234°
August
273°
239°
190°
279°
September
351°
309°
269°
268°
October
286°
349°
335°
270°
November
300°
259°
287°
273°
December
319°
335°
302°
294°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.