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
82.6
76
75
84
95
92
February
89.3
86
86
89
91
90
March
86.4
87
91
82
93
86
April
89.7
91
90
96
96
May
91.2
77
93
95
94
June
95.0
94
95
99
95
July
91.1
85
89
84
98
August
87.3
79
95
89
98
September
87.2
80
100
100
91
October
90.8
88
92
88
91
November
84.9
89
85
92
84
December
89.5
97
86
85
92
Average
88.4
82.9
85.6
90.5
92.4
92.7
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
-6.7
-9
-3
-5
-3
-10
February
-4.3
0
-2
-1
-4
0
March
2.5
3
1
4
7
0
April
9.3
12
8
12
8
May
18.2
22
15
17
16
June
21.2
23
20
25
20
July
22.9
23
24
25
22
August
22.2
23
25
23
22
September
17.2
19
22
19
18
October
9.9
11
15
10
6
November
0.3
5
-2
2
0
December
-5.2
1
-11
-12
-1
Average
7.9
-3.8
11.2
10.3
10.0
8.4
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
-14.6
-17
-10
-14
-11
-18
February
-15.7
-10
-11
-12
-19
-10
March
-10.8
-9
-12
-7
-6
-12
April
-3.2
-2
-3
-3
-4
May
4.9
8
3
4
4
June
8.9
10
9
10
9
July
11.0
11
12
12
11
August
10.0
10
12
10
9
September
5.2
5
6
6
6
October
-1.3
0
2
-1
-3
November
-8.3
-4
-10
-8
-8
December
-13.3
-9
-21
-19
-9
Average
-3.1
-13.9
-1.7
-2.8
-2.1
-2.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
23.0
32
12
35
15
24
February
27.0
15
31
32
28
21
March
21.0
25
21
16
12
32
April
14.2
8
19
5
12
May
9.7
7
14
12
14
June
10.6
12
14
2
8
July
9.5
6
10
4
15
August
7.1
13
4
9
4
September
9.4
3
2
6
5
October
11.9
11
6
6
23
November
18.5
2
25
9
20
December
16.5
1
27
29
11
Average
15.3
24.1
10.4
15.4
10.3
15.0
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
6.6
7
6
8
7
6
February
7.6
7
7
8
10
7
March
7.2
7
7
9
7
9
April
7.9
7
9
7
10
May
7.7
7
8
7
9
June
7.6
7
8
8
8
July
6.6
7
7
6
7
August
6.8
7
7
7
8
September
6.9
6
7
8
8
October
7.3
7
8
6
8
November
6.2
5
8
6
6
December
6.6
4
7
8
7
Average
7.1
6.8
6.5
7.7
7.3
7.8
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
302°
308°
301°
298°
297°
February
304°
297°
304°
294°
301°
March
349°
052°
315°
300°
303°
April
109°
341°
304°
307°
May
057°
303°
325°
334°
June
331°
322°
305°
308°
July
304°
317°
329°
296°
August
304°
292°
304°
293°
September
265°
297°
294°
304°
October
305°
290°
303°
303°
November
286°
301°
290°
292°
December
248°
296°
294°
291°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.