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
89.3
86
88
88
93
95
February
82.6
78
83
86
85
92
March
81.8
70
68
90
94
80
April
89.1
90
86
90
94
May
93.6
95
99
88
97
June
97.7
94
97
100
98
July
97.1
97
93
95
100
August
93.8
97
96
94
99
September
91.6
92
81
100
98
October
91.1
82
90
97
87
November
89.6
99
89
100
90
December
88.4
99
74
93
83
Average
89.4
77.5
89.9
89.9
93.8
93.1
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
0.6
-1
3
3
3
-1
February
-3.2
2
2
1
-7
4
March
4.3
5
-1
8
10
4
April
10.5
12
8
12
10
May
17.7
21
16
15
17
June
22.7
23
22
26
21
July
28.6
29
28
31
27
August
27.7
29
30
25
29
September
20.9
22
24
23
22
October
11.8
12
16
14
9
November
4.7
8
0
9
7
December
0.8
8
-8
-4
4
Average
11.1
1.8
14.0
13.0
13.1
12.6
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
-10.5
-13
-6
-10
-6
-10
February
-13.4
-8
-8
-10
-17
-7
March
-8.9
-7
-10
-4
-4
-7
April
-2.2
-1
-4
-1
-3
May
4.3
7
3
2
4
June
8.4
9
8
9
9
July
10.8
10
12
13
10
August
10.8
12
12
11
10
September
6.5
7
9
7
7
October
-1.6
0
2
1
-2
November
-5.2
-2
-10
-2
-2
December
-9.0
-4
-18
-14
-5
Average
-2.6
-10.4
1.1
-1.8
0.0
0.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
7.0
11
11
12
2
3
February
13.4
15
11
13
11
7
March
9.4
16
18
8
1
13
April
9.9
10
11
10
10
May
5.7
8
4
7
5
June
4.8
4
10
1
7
July
0.7
1
2
1
0
August
2.0
4
1
4
1
September
4.2
4
4
0
1
October
6.0
12
5
2
11
November
7.7
3
13
0
5
December
8.5
2
22
9
9
Average
7.1
13.9
7.4
7.9
3.9
5.7
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
13.9
12
13
18
15
13
February
13.8
11
19
18
13
17
March
11.8
10
9
14
14
15
April
12.5
12
13
13
13
May
10.8
8
15
10
12
June
11.5
9
14
12
12
July
9.0
8
9
9
11
August
9.2
9
8
11
10
September
10.6
10
11
12
12
October
12.7
9
12
14
12
November
15.3
15
15
19
17
December
13.5
12
13
14
14
Average
11.8
11.1
10.8
13.1
12.6
12.9
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
266°
268°
259°
249°
256°
February
287°
267°
274°
267°
262°
March
268°
311°
273°
254°
272°
April
267°
279°
279°
273°
May
290°
266°
282°
260°
June
266°
268°
274°
277°
July
260°
300°
288°
259°
August
259°
276°
271°
256°
September
263°
270°
255°
269°
October
283°
266°
251°
255°
November
252°
290°
251°
260°
December
246°
301°
257°
267°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.