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
82.6
80
85
80
92
74
February
81.5
83
85
78
88
83
March
81.6
70
85
71
87
86
April
79.3
70
82
92
91
May
83.5
87
70
94
86
June
75.4
56
81
85
70
July
77.2
52
94
76
72
August
79.6
75
79
74
89
September
83.0
81
86
82
76
October
82.8
79
91
79
87
November
89.5
91
92
96
85
December
82.7
67
85
82
86
Average
80.7
77.1
74.4
81.5
85.0
81.8
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
0.8
0
0
0
1
2
February
1.7
3
-1
3
1
2
March
4.9
6
6
6
6
6
April
10.0
11
11
12
8
May
15.7
18
16
17
15
June
20.2
18
20
24
21
July
23.9
23
26
22
24
August
23.6
22
24
24
24
September
20.1
21
20
20
20
October
14.7
16
14
15
15
November
8.2
8
10
9
11
December
3.4
6
5
5
4
Average
11.2
3.1
12.3
13.0
13.0
12.7
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
-7.5
-7
0
-11
-5
-6
February
-7.8
-5
-3
-8
-8
-6
March
-3.0
-1
-2
-3
-4
-2
April
1.9
2
3
3
1
May
6.8
7
8
8
6
June
11.4
11
11
14
12
July
15.4
17
16
15
16
August
14.8
15
16
16
14
September
11.6
13
11
13
11
October
6.5
8
7
7
5
November
-1.7
-1
2
0
1
December
-5.6
-2
-1
-4
-3
Average
3.1
-5.9
5.4
4.4
4.6
4.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
17.7
25
21
25
12
11
February
15.3
9
17
22
13
13
March
14.6
24
18
16
9
10
April
14.7
14
14
9
16
May
8.0
6
6
7
6
June
8.2
13
8
4
6
July
5.5
8
2
10
3
August
5.4
11
5
5
4
September
5.1
7
5
7
4
October
11.3
15
5
14
7
November
12.6
10
9
8
10
December
16.1
18
24
18
13
Average
11.5
19.2
12.4
10.4
9.0
8.1
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
8.3
8
8
9
8
7
February
8.5
8
8
9
8
8
March
9.0
10
9
8
9
9
April
8.6
9
9
8
10
May
7.7
8
8
8
9
June
6.2
6
6
7
6
July
5.6
5
6
6
6
August
5.7
6
5
5
7
September
6.1
5
7
6
7
October
7.0
6
7
7
8
November
8.2
7
9
7
8
December
7.8
7
10
7
9
Average
7.5
8.8
6.8
7.5
7.0
7.7
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
346°
342°
298°
340°
289°
February
284°
309°
267°
308°
266°
March
305°
322°
260°
256°
262°
April
130°
275°
306°
318°
May
241°
175°
241°
238°
June
107°
205°
223°
181°
July
174°
219°
193°
185°
August
200°
153°
155°
218°
September
219°
253°
212°
201°
October
224°
178°
053°
238°
November
263°
251°
267°
243°
December
264°
298°
284°
255°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.