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
78.4
65
63
76
92
90
February
77.9
87
71
73
77
79
March
80.4
65
83
73
87
83
April
83.8
85
76
92
90
87
May
88.4
94
83
93
93
June
88.7
81
90
93
92
July
86.4
77
97
75
87
August
88.1
80
92
86
94
September
85.7
82
78
89
89
October
80.9
83
76
80
79
November
87.2
91
86
92
90
December
78.0
68
77
76
85
Average
83.4
75.2
79.3
83.6
86.1
87.8
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
0.9
1
4
-1
0
3
February
3.1
5
4
3
0
3
March
6.6
9
7
8
9
9
April
12.9
14
15
13
14
11
May
19.9
21
22
20
19
June
24.6
23
24
27
25
July
27.5
28
28
25
28
August
26.4
25
29
27
26
September
22.3
23
22
22
22
October
16.1
18
17
17
14
November
8.3
8
11
9
11
December
3.4
7
5
5
4
Average
13.5
7.0
15.2
15.4
14.6
14.5
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
-8.6
-6
-3
-13
-7
-6
February
-7.3
-5
-6
-7
-9
-6
March
-4.8
0
-2
-3
-3
-1
April
2.4
3
4
2
2
1
May
7.8
6
9
8
7
June
13.0
13
13
15
13
July
16.6
18
17
16
17
August
15.9
15
17
18
15
September
11.8
13
12
13
10
October
6.5
8
5
9
5
November
-1.3
-1
2
-1
0
December
-5.4
-1
-3
-3
-5
Average
3.5
-3.8
5.3
4.5
4.8
4.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
14.1
20
26
17
7
5
February
13.5
6
20
17
17
11
March
12.5
16
15
10
6
12
April
13.7
16
10
8
11
26
May
8.0
8
4
8
5
June
8.2
13
6
4
11
July
6.7
12
5
12
2
August
5.2
10
4
6
3
September
7.8
14
11
7
3
October
12.0
11
12
12
13
November
10.6
7
14
5
9
December
14.3
14
17
10
15
Average
10.6
14.7
12.7
9.3
8.4
9.2
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
4.9
4
4
5
5
5
February
5.3
5
5
6
5
5
March
5.6
5
5
5
6
5
April
5.4
5
5
6
5
6
May
4.9
5
5
5
6
June
4.5
3
5
5
4
July
3.9
4
5
3
4
August
3.9
4
4
3
4
September
3.7
3
4
4
5
October
4.2
4
4
4
4
November
5.3
5
6
5
5
December
4.9
4
5
4
6
Average
4.7
4.7
4.1
4.9
4.6
4.9
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
262°
251°
251°
291°
246°
February
254°
254°
237°
278°
252°
March
275°
278°
263°
264°
251°
April
244°
261°
268°
289°
259°
May
260°
211°
262°
251°
June
206°
233°
224°
231°
July
212°
222°
228°
216°
August
229°
221°
223°
243°
September
244°
252°
212°
213°
October
222°
213°
245°
218°
November
248°
232°
247°
237°
December
228°
249°
245°
232°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.