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
72.5
61
56
86
79
71
February
83.8
91
85
86
83
89
March
87.9
91
86
85
94
77
April
90.0
88
91
87
99
89
May
90.9
92
85
98
88
June
91.7
83
94
95
99
July
94.4
84
95
97
96
August
94.3
91
96
98
97
September
92.1
89
91
99
86
October
88.4
85
92
88
94
November
89.3
93
84
97
91
December
82.1
69
71
88
99
Average
88.2
83.6
84.1
88.6
93.7
89.9
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
-1.5
-2
2
-3
0
2
February
2.9
9
5
1
-5
1
March
9.0
12
8
10
11
10
April
15.2
17
17
13
17
15
May
22.0
23
23
21
20
June
27.9
28
28
29
29
July
28.5
28
28
27
30
August
27.7
27
27
29
29
September
25.0
24
24
27
23
October
16.9
17
17
19
16
November
8.3
10
11
9
13
December
4.2
6
3
7
4
Average
14.8
8.7
16.2
15.6
16.0
15.8
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
-8.3
-7
-4
-14
-7
-5
February
-7.1
-3
-5
-9
-14
-7
March
-1.3
1
-1
-1
0
0
April
3.6
5
3
4
4
3
May
10.4
9
12
9
10
June
15.6
13
16
17
17
July
17.5
16
17
17
19
August
15.9
16
16
17
16
September
13.0
13
12
13
12
October
6.0
7
4
11
3
November
-2.6
-2
-1
-2
2
December
-4.2
0
-4
-3
-5
Average
4.4
-1.0
5.5
4.7
5.3
5.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
12.3
15
23
10
9
9
February
8.4
0
12
7
13
10
March
8.4
9
11
16
5
12
April
10.1
14
10
10
7
11
May
7.7
8
11
7
8
June
4.6
3
6
5
3
July
3.9
6
6
7
4
August
3.1
3
6
1
1
September
5.5
11
5
2
7
October
8.7
11
6
14
7
November
7.5
5
16
5
6
December
8.2
13
17
6
4
Average
7.4
10.0
9.3
9.0
6.3
6.6
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
9.8
9
9
11
9
9
February
10.4
10
11
11
10
11
March
11.0
12
11
11
12
10
April
11.3
12
12
13
11
11
May
9.4
9
11
10
9
June
8.3
8
8
8
8
July
6.6
6
7
7
6
August
6.4
6
7
6
6
September
7.2
6
7
8
8
October
9.2
9
9
8
10
November
9.9
9
11
11
11
December
9.6
9
10
11
9
Average
9.2
10.7
8.6
9.5
8.9
8.9
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
266°
263°
286°
293°
247°
February
257°
250°
267°
292°
295°
March
263°
275°
276°
183°
239°
April
259°
239°
214°
251°
283°
May
064°
132°
171°
058°
June
030°
234°
216°
172°
July
266°
243°
289°
226°
August
304°
234°
196°
240°
September
123°
291°
240°
234°
October
271°
236°
036°
268°
November
247°
223°
241°
223°
December
252°
189°
236°
262°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.