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
79.0
77
68
82
87
84
February
81.3
86
80
82
81
77
March
86.2
89
84
80
95
82
April
86.0
85
83
94
94
May
93.4
96
91
97
97
June
92.0
85
93
95
97
July
94.6
85
96
97
96
August
93.4
90
93
95
92
September
91.2
93
87
96
94
October
87.4
88
97
87
88
November
85.7
88
87
87
88
December
79.7
78
76
80
78
Average
87.8
84.5
85.6
87.9
91.8
89.7
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
-5.2
-3
-2
-9
-4
-3
February
-3.5
0
-3
-4
-4
-2
March
2.5
6
3
2
5
3
April
10.5
12
10
14
10
May
19.4
20
21
20
19
June
23.6
24
23
26
25
July
26.2
26
26
24
28
August
24.9
24
25
27
24
September
20.8
22
19
21
19
October
14.0
15
15
15
12
November
4.4
4
7
5
8
December
-2.4
1
2
-1
0
Average
10.2
0.9
12.1
11.9
12.4
11.9
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
-13.5
-10
-9
-20
-11
-10
February
-12.1
-8
-13
-14
-13
-12
March
-6.1
-3
-5
-6
-6
-5
April
0.9
2
1
3
0
May
7.5
6
10
7
7
June
12.7
13
13
15
12
July
15.8
17
15
15
17
August
14.8
14
15
17
14
September
10.6
12
10
11
9
October
5.0
8
3
7
3
November
-3.1
-3
-1
-2
-1
December
-9.7
-5
-5
-9
-7
Average
1.0
-7.0
3.2
2.1
2.9
2.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
34.5
34
42
35
26
24
February
30.0
21
32
36
26
32
March
22.2
24
28
29
11
22
April
22.1
20
22
15
19
May
10.8
11
11
3
5
June
10.7
10
15
8
5
July
6.8
11
7
6
7
August
8.1
9
13
6
12
September
8.8
4
15
7
8
October
16.3
26
9
16
15
November
21.9
22
20
13
13
December
32.1
32
34
22
28
Average
18.5
26.0
19.2
19.0
12.1
14.7
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
5.6
6
5
5
5
5
February
6.2
5
6
7
6
7
March
6.5
6
7
6
7
6
April
7.0
6
7
7
8
May
6.3
6
6
6
7
June
5.4
4
5
6
6
July
4.7
4
5
5
4
August
4.6
4
4
4
5
September
4.5
4
4
5
5
October
5.3
4
4
5
5
November
5.7
5
6
5
6
December
5.5
4
6
5
6
Average
5.6
5.6
5.0
5.4
5.5
5.7
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
291°
298°
315°
256°
271°
February
267°
296°
287°
261°
247°
March
299°
278°
270°
266°
296°
April
210°
327°
341°
279°
May
293°
136°
277°
269°
June
058°
257°
241°
247°
July
227°
243°
239°
230°
August
257°
237°
238°
253°
September
224°
305°
252°
237°
October
240°
214°
049°
253°
November
256°
241°
257°
276°
December
010°
335°
301°
277°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.