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
86.3
91
81
59
93
95
February
83.0
80
75
85
81
82
March
83.3
74
70
90
88
85
April
87.6
88
88
82
88
92
May
90.6
92
89
93
96
June
97.4
93
99
100
99
July
98.5
99
98
100
100
August
97.2
94
99
97
99
September
90.8
92
98
77
97
October
87.4
81
90
89
86
November
87.8
91
76
100
98
December
88.9
95
63
87
96
Average
89.5
82.9
87.6
87.0
91.2
93.8
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
3.1
2
1
5
4
5
February
1.1
6
2
4
-4
1
March
7.6
8
2
9
9
8
April
12.4
14
12
11
13
11
May
18.0
21
17
19
18
June
24.6
22
25
30
26
July
29.9
27
32
32
31
August
28.8
28
31
29
31
September
22.2
17
26
22
24
October
13.8
13
16
16
13
November
8.4
10
4
12
11
December
4.6
7
0
6
7
Average
13.7
7.4
13.4
15.4
15.7
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
-7.2
-9
-6
-7
-5
-6
February
-10.7
-4
-8
-8
-13
-8
March
-4.7
-3
-8
-3
-2
-3
April
0.2
2
0
-2
0
-1
May
6.3
9
6
5
6
June
11.5
12
11
14
12
July
15.5
15
16
18
15
August
14.7
15
17
14
15
September
9.2
8
11
7
10
October
2.0
2
5
4
1
November
-3.8
-1
-5
1
-1
December
-6.6
-3
-9
-7
-4
Average
1.9
-4.1
2.9
3.1
3.1
2.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.0
7
21
12
7
6
February
14.7
12
27
13
17
15
March
11.3
14
26
7
10
4
April
14.0
14
14
22
12
13
May
10.1
14
16
6
6
June
4.4
12
2
3
3
July
2.1
3
2
1
2
August
2.4
7
3
2
1
September
3.3
2
3
1
3
October
10.1
14
4
12
11
November
8.8
8
18
1
1
December
7.8
5
26
7
5
Average
8.4
11.6
12.5
10.1
6.1
5.6
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
7.5
6
7
9
8
8
February
8.2
7
9
10
9
8
March
9.1
8
10
11
8
9
April
11.2
13
10
15
10
11
May
9.7
9
12
9
10
June
8.4
7
8
9
9
July
7.3
7
7
8
9
August
7.5
8
7
9
7
September
7.8
7
8
7
8
October
9.0
8
9
10
10
November
8.2
7
10
8
7
December
8.7
8
11
10
9
Average
8.6
8.8
8.0
9.8
8.7
8.8
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
354°
337°
337°
322°
314°
February
293°
335°
339°
331°
322°
March
353°
351°
345°
320°
340°
April
341°
350°
334°
347°
342°
May
341°
327°
349°
349°
June
336°
357°
336°
348°
July
350°
348°
346°
350°
August
350°
349°
355°
348°
September
357°
347°
334°
347°
October
342°
348°
326°
339°
November
025°
338°
334°
196°
December
344°
345°
261°
315°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.