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
77.7
85
67
71
89
77
February
81.9
82
84
72
88
90
March
79.3
68
79
69
84
85
April
84.4
85
80
93
91
May
91.9
98
87
96
90
June
90.7
89
86
93
94
July
91.1
82
95
94
85
August
89.6
76
93
91
93
September
89.2
81
88
89
95
October
85.3
78
88
88
86
November
84.4
83
81
91
86
December
79.9
75
71
75
84
Average
85.4
76.8
81.8
82.8
89.9
88.5
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
-5.4
-4
-3
-8
-3
-4
February
-3.0
-1
-4
-4
-3
-3
March
1.7
3
2
1
4
2
April
8.7
10
8
12
7
May
17.6
18
19
18
17
June
22.3
21
21
24
25
July
25.8
27
26
24
26
August
24.5
22
24
26
25
September
20.2
22
19
20
21
October
13.4
15
16
15
11
November
3.8
3
6
5
7
December
-2.3
1
1
-2
1
Average
9.4
-1.7
11.2
11.2
11.6
11.3
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
-14.9
-12
-10
-19
-9
-12
February
-14.6
-10
-16
-14
-13
-13
March
-8.7
-4
-6
-7
-7
-8
April
-1.7
0
0
1
-2
May
5.5
5
7
6
5
June
11.1
12
10
13
12
July
14.8
17
14
13
16
August
13.6
13
15
16
13
September
9.4
11
9
11
8
October
4.4
7
5
5
3
November
-4.5
-4
-2
-2
-1
December
-10.8
-6
-5
-10
-7
Average
-1.8
-9.1
2.1
1.2
1.9
1.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
23.1
21
39
27
14
20
February
16.8
12
15
31
15
12
March
21.3
37
25
26
16
14
April
15.8
11
26
16
12
May
13.0
14
16
13
12
June
10.8
18
16
7
5
July
5.7
5
7
7
6
August
8.0
19
9
5
7
September
9.6
16
10
11
2
October
11.3
16
7
7
14
November
16.8
19
21
10
12
December
19.3
30
33
16
12
Average
14.6
24.9
18.1
17.9
11.0
9.8
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
6.9
7
7
7
6
6
February
7.4
8
7
8
7
7
March
8.0
7
7
8
9
8
April
7.8
7
8
9
9
May
7.7
8
7
7
8
June
6.7
6
7
7
7
July
5.8
5
7
6
6
August
5.6
6
5
5
6
September
6.2
5
6
7
8
October
6.7
6
6
5
7
November
7.1
7
8
6
7
December
7.3
7
10
7
8
Average
6.9
7.3
6.4
7.0
6.8
7.2
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
278°
347°
318°
324°
318°
February
262°
316°
304°
313°
260°
March
324°
335°
294°
270°
309°
April
228°
331°
356°
308°
May
326°
235°
315°
298°
June
058°
216°
241°
233°
July
184°
247°
260°
184°
August
200°
218°
207°
259°
September
338°
295°
229°
232°
October
216°
196°
354°
257°
November
267°
279°
276°
239°
December
294°
349°
293°
247°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.