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
68.5
65
46
84
64
70
February
85.0
77
91
73
91
89
March
87.4
76
86
79
97
87
April
85.3
83
71
79
92
May
90.7
94
86
93
91
June
95.6
95
96
98
94
July
95.6
95
97
94
99
August
94.4
92
93
89
97
September
89.1
91
87
95
93
October
81.6
74
89
81
94
November
80.0
79
79
89
85
December
68.2
66
67
73
60
Average
85.1
73.3
84.0
84.5
87.8
88.9
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
-10.0
-9
-8
-15
-6
-8
February
-9.5
-3
-7
-13
-11
-7
March
0.2
-1
-2
-2
5
2
April
6.7
6
4
9
7
May
17.3
21
16
18
17
June
23.2
25
22
24
23
July
25.2
23
24
27
27
August
23.4
23
24
25
24
September
17.7
20
18
20
16
October
8.5
9
11
13
5
November
-2.6
0
0
1
1
December
-8.8
-1
-7
-8
-6
Average
6.5
-5.6
9.0
7.4
9.8
8.3
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
-19.7
-16
-14
-26
-14
-16
February
-20.0
-13
-19
-27
-23
-19
March
-13.7
-13
-15
-13
-8
-11
April
-6.9
-6
-5
-3
-5
May
4.1
6
5
5
4
June
10.7
13
10
12
11
July
13.2
12
13
14
15
August
12.3
12
13
15
13
September
8.2
10
7
10
7
October
1.7
2
2
6
-2
November
-8.0
-7
-6
-5
-6
December
-16.3
-8
-15
-18
-14
Average
-4.2
-14.1
-2.9
-3.1
-1.3
-2.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
52.8
56
64
52
47
55
February
42.9
45
39
53
43
40
March
23.9
38
20
42
12
25
April
24.2
27
45
25
23
May
14.2
6
27
17
12
June
10.2
8
15
7
13
July
7.8
11
12
3
5
August
7.3
11
5
5
7
September
15.1
5
16
12
14
October
32.3
31
26
24
29
November
50.0
41
48
45
27
December
50.7
40
63
51
58
Average
27.2
45.1
22.8
30.6
21.5
23.3
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
5.8
6
6
7
5
5
February
6.8
6
7
7
7
7
March
7.1
8
7
7
7
7
April
6.8
7
7
7
8
May
6.5
7
7
7
7
June
6.3
5
8
7
7
July
6.3
6
6
6
7
August
6.3
6
6
7
6
September
6.5
6
6
7
8
October
6.7
6
7
6
7
November
7.4
8
7
8
7
December
5.7
6
6
6
6
Average
6.6
6.8
6.3
7.0
6.8
6.9
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
258°
271°
259°
231°
258°
February
291°
265°
275°
259°
275°
March
311°
324°
307°
254°
255°
April
029°
037°
353°
288°
May
153°
185°
269°
291°
June
170°
267°
266°
233°
July
281°
285°
270°
248°
August
265°
261°
236°
248°
September
153°
250°
247°
275°
October
318°
259°
234°
256°
November
270°
287°
298°
272°
December
230°
118°
251°
268°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.