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
82.8
77
69
74
91
91
February
83.1
87
83
81
83
81
March
82.2
67
79
79
87
87
April
84.1
74
88
94
92
May
89.4
92
85
97
94
June
85.4
68
86
96
86
July
86.6
69
95
84
86
August
87.4
78
84
84
96
September
89.1
84
85
89
87
October
81.2
83
75
83
85
November
88.6
94
85
95
88
December
77.8
65
76
75
78
Average
84.3
76.0
77.7
83.6
88.6
88.2
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
-1.9
0
0
-2
1
2
February
1.5
4
-1
1
0
2
March
5.4
7
6
7
7
7
April
11.7
13
12
14
10
May
18.9
20
21
19
19
June
23.5
22
23
26
24
July
26.5
27
28
24
27
August
25.6
24
26
27
26
September
21.9
23
20
22
22
October
15.4
17
16
16
14
November
7.5
7
11
9
10
December
2.3
5
5
3
3
Average
12.2
3.6
13.5
14.6
13.8
13.8
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
-9.6
-8
0
-14
-7
-8
February
-8.0
-7
-3
-11
-10
-9
March
-5.6
-1
-3
-4
-4
-3
April
1.5
2
2
2
0
May
6.5
6
7
7
6
June
11.8
12
11
14
12
July
15.7
18
15
15
17
August
14.4
15
15
17
15
September
10.9
13
10
12
9
October
5.3
7
4
7
4
November
-3.7
-3
0
-2
-1
December
-7.6
-4
-3
-6
-4
Average
2.1
-6.7
4.8
3.1
3.7
3.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
17.1
25
31
22
9
10
February
15.4
8
17
23
17
13
March
15.1
28
20
16
8
12
April
17.6
19
21
15
18
May
9.6
9
9
8
4
June
11.2
24
8
4
10
July
8.2
17
4
16
5
August
7.1
15
8
7
4
September
6.8
8
13
7
2
October
14.7
15
13
14
14
November
12.5
12
15
8
10
December
16.7
25
27
13
15
Average
13.1
21.1
17.4
13.1
10.2
9.2
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
6.7
7
6
8
7
5
February
6.8
8
7
8
7
6
March
8.2
8
9
7
8
8
April
7.8
7
9
9
9
May
7.3
8
6
7
9
June
6.1
5
6
6
6
July
5.3
5
6
5
5
August
5.2
5
5
5
5
September
5.7
4
6
6
7
October
6.0
5
5
6
6
November
6.6
6
7
6
6
December
6.1
5
9
5
7
Average
6.6
7.5
6.0
6.5
6.4
6.7
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
339°
350°
333°
335°
318°
February
315°
333°
319°
325°
298°
March
333°
332°
304°
296°
327°
April
307°
313°
329°
323°
May
315°
182°
310°
279°
June
056°
216°
217°
211°
July
169°
238°
351°
192°
August
235°
326°
212°
256°
September
339°
312°
258°
210°
October
295°
144°
354°
286°
November
296°
272°
300°
283°
December
334°
337°
321°
284°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.