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
80.3
71
66
77
86
89
February
84.4
48
91
95
90
97
March
82.5
85
71
87
87
85
April
91.6
86
93
94
94
96
May
90.7
87
96
92
97
June
95.6
93
92
100
100
July
96.1
93
97
90
99
August
96.6
100
95
98
98
September
93.3
87
94
98
98
October
91.5
82
97
92
94
November
93.1
89
94
99
98
December
79.1
75
53
73
92
Average
88.6
73.0
85.9
90.6
92.0
95.4
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
2.7
-1
-1
6
5
4
February
3.4
10
2
7
-2
7
March
10.2
11
6
12
14
11
April
16.3
16
16
17
17
17
May
22.4
24
23
22
21
June
29.9
28
30
32
31
July
32.6
30
34
33
33
August
31.3
31
32
33
34
September
27.7
28
30
29
28
October
17.0
17
19
20
16
November
11.8
14
8
15
15
December
5.1
7
-1
7
8
Average
16.6
9.1
16.8
18.6
18.9
18.8
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
-9.1
-13
-10
-8
-5
-7
February
-10.2
-5
-10
-10
-12
-7
March
-4.4
-4
-6
-5
-1
-2
April
0.9
3
0
1
1
0
May
8.5
10
9
8
8
June
15.0
14
14
16
17
July
17.9
15
18
19
18
August
15.9
16
16
17
17
September
11.6
11
11
13
10
October
2.0
3
2
5
0
November
-4.6
-2
-8
0
-2
December
-8.5
-6
-11
-7
-6
Average
2.3
-5.2
3.1
2.9
4.6
3.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.1
14
22
0
6
5
February
9.1
16
8
5
10
3
March
8.5
7
13
8
9
5
April
8.4
15
7
11
9
5
May
6.7
4
4
3
7
June
2.7
3
3
2
1
July
1.2
2
1
1
1
August
1.4
2
1
1
0
September
1.3
1
0
2
1
October
6.7
11
4
0
5
November
4.3
6
3
3
1
December
11.7
16
28
6
5
Average
6.3
12.6
7.4
4.9
4.2
3.0
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
9.5
9
8
12
10
9
February
9.7
9
10
12
7
10
March
10.7
11
10
12
11
12
April
12.4
12
13
15
12
12
May
10.1
10
10
10
10
June
9.6
8
10
9
11
July
8.8
7
9
9
10
August
8.9
9
9
9
10
September
9.4
8
9
9
10
October
10.8
11
10
11
11
November
10.1
9
11
11
10
December
9.8
10
12
9
10
Average
10.1
10.6
9.3
10.8
9.7
10.4
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
302°
304°
291°
292°
272°
February
296°
287°
299°
275°
289°
March
326°
331°
328°
290°
262°
April
321°
317°
302°
320°
302°
May
163°
292°
131°
139°
June
170°
194°
188°
167°
July
187°
186°
153°
162°
August
254°
178°
169°
172°
September
189°
227°
234°
279°
October
316°
298°
284°
297°
November
297°
298°
290°
251°
December
298°
316°
290°
300°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.