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
95.0
94
98
94
94
97
February
89.0
92
91
91
81
97
March
90.4
88
80
95
99
89
April
94.6
96
97
96
92
94
May
95.3
99
96
100
92
97
June
99.4
100
100
100
99
July
99.8
100
100
100
100
100
August
98.6
100
97
98
99
100
September
97.7
96
100
100
98
October
91.6
91
93
94
84
November
95.6
97
95
100
98
December
95.4
98
91
89
100
Average
95.4
96.3
94.3
96.4
95.3
96.0
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
2.6
0
2
3
4
3
February
-1.7
4
3
3
-6
4
March
5.7
7
0
10
10
6
April
11.1
14
11
8
12
11
May
16.0
16
18
16
16
17
June
23.6
24
23
28
23
July
27.7
30
2
29
32
27
August
27.1
29
22
30
27
30
September
23.1
20
27
25
24
October
10.9
6
16
16
9
November
7.0
10
1
11
9
December
3.2
8
-3
1
5
Average
11.5
14.7
9.3
13.5
14.5
14.1
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
-7.3
-10
-6
-7
-3
-7
February
-10.0
-5
-7
-9
-14
-6
March
-6.5
-4
-8
-4
-4
-5
April
-2.9
1
-1
-4
-1
-3
May
3.6
3
6
4
3
4
June
8.6
8
8
10
9
July
12.2
13
0
14
15
11
August
10.4
12
4
14
11
11
September
7.7
7
10
7
7
October
0.2
-2
4
3
-2
November
-4.7
-1
-7
-1
-3
December
-7.6
-3
-13
-10
-3
Average
-1.7
1.6
-2.7
0.9
1.3
1.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.1
9
6
14
12
5
February
19.6
17
12
17
26
13
March
12.9
12
24
9
2
17
April
13.0
8
11
13
15
12
May
10.6
8
9
12
7
8
June
6.3
4
5
2
12
July
2.7
2
2
4
2
3
August
3.4
2
5
4
6
1
September
5.7
6
5
1
3
October
11.5
11
8
9
21
November
9.0
7
13
1
4
December
6.6
2
14
13
1
Average
9.2
7.6
9.1
9.6
7.3
8.2
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
16.0
12
17
19
16
15
February
15.1
12
17
20
14
17
March
12.1
9
10
17
13
14
April
12.9
12
12
15
13
13
May
11.2
15
8
13
11
10
June
11.5
12
13
11
12
July
9.0
9
7
9
9
10
August
10.2
11
10
10
12
10
September
11.5
10
9
13
13
October
13.0
11
12
12
15
November
15.8
13
16
18
16
December
14.0
13
12
13
16
Average
12.9
11.5
11.5
13.8
12.7
13.0
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
265°
270°
285°
273°
280°
February
270°
276°
286°
307°
287°
March
267°
307°
301°
294°
288°
April
262°
284°
301°
313°
301°
May
263°
304°
288°
316°
277°
June
258°
271°
301°
293°
July
290°
329°
284°
311°
290°
August
289°
272°
283°
301°
291°
September
276°
282°
287°
289°
October
289°
282°
292°
293°
November
234°
278°
277°
280°
December
219°
293°
289°
277°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.