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
79.7
64
73
96
79
84
February
86.5
91
82
95
90
94
March
87.3
87
81
83
97
82
April
88.2
88
90
89
95
87
May
89.7
94
91
95
86
June
91.7
82
91
96
100
July
96.4
97
92
94
99
August
96.4
95
93
95
99
September
93.7
93
94
99
96
October
92.1
92
95
89
94
November
92.6
92
90
98
94
December
86.4
84
80
87
96
Average
89.7
83.0
88.3
90.9
93.3
92.6
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
0.3
0
3
-2
1
2
February
2.7
8
4
2
-3
2
March
7.0
9
6
8
10
8
April
13.0
15
16
12
15
11
May
19.1
19
20
20
17
June
25.4
25
27
28
26
July
27.8
28
28
27
29
August
26.9
27
27
29
28
September
23.5
24
23
25
22
October
16.2
17
17
19
14
November
8.6
10
11
9
13
December
4.1
7
4
6
4
Average
13.7
7.8
15.4
15.0
15.4
14.6
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
-6.2
-4
-2
-10
-5
-4
February
-6.6
-1
-4
-7
-10
-5
March
-1.6
1
-1
-1
2
1
April
4.1
6
5
4
6
3
May
9.9
10
12
11
9
June
15.8
15
17
18
16
July
19.6
19
19
19
21
August
18.8
19
19
19
19
September
15.4
16
15
16
14
October
8.2
10
7
13
5
November
1.3
2
3
1
5
December
-3.9
2
-1
-1
-3
Average
5.8
0.3
7.7
6.6
7.4
6.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
18.0
23
28
10
15
14
February
11.8
3
19
11
9
9
March
11.2
13
20
19
5
11
April
12.7
14
12
15
7
13
May
8.2
8
6
7
11
June
5.3
5
6
3
5
July
2.8
5
5
1
1
August
3.2
3
3
2
1
September
6.7
10
7
1
11
October
10.0
15
5
10
10
November
10.4
10
19
9
7
December
11.9
17
21
9
7
Average
9.4
13.5
11.9
9.8
5.9
8.0
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
9.2
9
9
10
9
9
February
10.1
10
11
11
9
11
March
10.4
11
10
10
11
11
April
10.5
11
11
11
10
10
May
9.4
9
10
10
10
June
8.9
8
9
9
9
July
8.4
8
9
9
8
August
8.3
9
9
8
8
September
8.8
9
9
9
10
October
9.8
10
9
9
10
November
10.0
10
11
10
11
December
9.4
9
10
10
9
Average
9.5
10.4
9.2
9.8
9.3
9.5
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
289°
269°
277°
301°
264°
February
263°
270°
264°
281°
288°
March
305°
356°
314°
213°
239°
April
288°
233°
208°
153°
322°
May
054°
123°
157°
058°
June
037°
250°
197°
131°
July
084°
289°
349°
077°
August
045°
011°
163°
178°
September
138°
315°
277°
227°
October
263°
247°
049°
278°
November
256°
238°
251°
241°
December
270°
185°
242°
275°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.