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
63.4
58
41
85
66
56
February
80.2
86
81
75
88
91
March
81.4
80
71
81
89
81
April
74.1
70
63
73
87
May
86.4
89
85
89
95
June
89.1
79
92
95
94
July
91.4
96
89
88
91
August
83.0
82
83
82
87
September
79.1
68
84
95
85
October
81.4
79
93
73
88
November
78.6
81
68
93
87
December
63.1
58
54
73
73
Average
79.2
74.6
74.9
80.3
84.2
84.9
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
-6.0
-5
-5
-9
-3
-5
February
-5.6
3
-3
-8
-9
-4
March
2.3
4
0
1
6
3
April
7.8
6
5
10
8
May
17.4
19
17
19
16
June
23.3
24
24
26
24
July
25.7
25
25
27
27
August
24.1
25
25
26
24
September
19.7
21
20
22
18
October
11.3
12
14
14
7
November
2.2
4
3
4
6
December
-3.1
3
-3
-2
-3
Average
8.9
0.8
10.9
9.8
11.5
10.0
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
-14.4
-11
-10
-20
-11
-12
February
-14.0
-7
-13
-19
-18
-14
March
-7.3
-6
-9
-8
-3
-4
April
-1.0
-1
-2
1
-2
May
6.3
7
7
7
6
June
11.5
12
9
14
13
July
14.9
14
14
15
16
August
14.4
14
15
16
15
September
10.6
13
10
11
7
October
3.8
5
3
7
1
November
-5.1
-4
-4
-4
-3
December
-10.1
-4
-10
-11
-10
Average
-1.8
-9.9
1.8
0.1
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
31.0
39
38
24
17
38
February
24.0
12
24
35
13
26
March
19.2
21
31
24
9
23
April
24.2
32
37
18
11
May
9.9
6
15
2
4
June
7.0
8
6
5
4
July
4.3
3
5
3
7
August
9.0
8
4
6
8
September
11.4
14
9
5
9
October
17.9
15
11
13
20
November
26.2
19
35
16
14
December
32.3
29
47
29
18
Average
18.4
23.7
18.2
19.0
10.4
14.4
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
9.2
8
9
11
8
9
February
10.4
10
10
11
10
11
March
10.7
11
11
11
10
10
April
10.9
12
11
9
11
May
10.1
10
10
10
11
June
9.2
9
11
8
10
July
7.7
7
9
7
8
August
8.4
8
8
10
8
September
9.1
9
8
9
10
October
10.1
9
10
8
11
November
10.3
11
10
11
10
December
9.4
9
9
11
8
Average
9.7
9.8
9.3
9.9
9.1
9.9
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
285°
324°
279°
302°
295°
February
292°
292°
304°
274°
279°
March
330°
047°
322°
234°
303°
April
025°
040°
348°
319°
May
093°
146°
207°
019°
June
095°
260°
226°
334°
July
300°
267°
117°
262°
August
117°
202°
237°
251°
September
105°
222°
245°
267°
October
343°
280°
102°
275°
November
266°
298°
288°
263°
December
245°
106°
268°
285°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.