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
90.5
83
91
96
February
90.3
82
93
94
March
95.0
94
96
95
April
93.4
100
89
May
92.7
95
91
June
98.3
99
98
July
99.7
100
98
100
August
89.1
100
100
64
September
98.5
99
October
95.7
96
November
92.5
100
89
100
December
92.0
98
90
90
Average
86.1
86.6
96.6
93.7
90.2
63.6
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
-2
3
2
February
4.3
6
4
4
March
6.8
7
3
11
April
12.4
14
11
May
20.9
23
19
June
24.9
26
24
July
29.7
32
30
0
August
33.0
36
31
32
September
28.6
29
October
17.2
17
November
4.7
8
3
0
December
0.9
8
-5
-2
Average
11.9
3.6
13.6
12.2
-2.3
32.0
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
-10.9
-13
-6
-9
February
-7.7
-3
-7
-9
March
-4.4
-3
-5
-2
April
0.8
3
-1
May
9.2
11
8
June
13.9
14
13
July
17.0
17
21
0
August
22.5
25
20
23
September
12.7
13
October
4.9
5
November
-4.0
0
-7
0
December
-9.5
-3
-14
-10
Average
2.2
-7.7
2.9
0.5
-10.8
23.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
0.0
0
0
0
February
0.0
0
0
0
March
0.0
0
0
0
April
0.0
0
0
May
0.0
0
0
June
0.0
0
0
July
0.0
0
0
0
August
0.0
0
0
0
September
0.0
0
October
0.0
0
November
0.0
0
0
0
December
0.0
0
0
0
Average
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
5.4
4
5
7
February
7.5
6
8
9
March
7.8
6
8
9
April
9.8
9
11
May
7.1
6
8
June
5.9
6
6
July
5.6
6
5
0
August
6.8
6
9
4
September
6.2
6
October
6.8
7
November
6.9
6
8
0
December
3.3
5
5
2
Average
5.0
5.4
6.4
7.6
1.8
3.9
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
287°
263°
268°
February
284°
271°
278°
March
011°
035°
289°
April
283°
299°
May
054°
285°
June
059°
249°
July
287°
071°
360°
August
273°
280°
048°
September
298°
October
280°
November
265°
271°
360°
December
275°
296°
278°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.