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
80.7
85
70
75
89
87
February
83.7
85
89
82
87
81
March
82.1
71
81
78
89
87
April
83.9
83
87
94
93
May
89.4
95
86
95
90
June
84.7
66
85
93
86
July
86.7
77
97
81
81
August
87.8
87
86
83
92
September
86.3
79
84
87
87
October
84.8
84
80
91
89
November
87.8
94
85
94
87
December
80.5
66
78
79
85
Average
84.6
79.2
80.6
84.1
88.6
87.2
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
-1.4
0
2
-3
-1
0
February
0.9
2
0
2
-1
1
March
4.8
6
5
6
7
6
April
11.7
13
12
14
10
May
18.7
20
21
19
19
June
23.2
22
23
26
25
July
26.8
27
28
24
27
August
25.9
24
27
27
26
September
21.9
23
21
22
22
October
15.6
17
17
17
14
November
7.3
7
10
8
10
December
1.7
4
5
2
3
Average
11.9
2.6
13.7
14.3
13.7
13.6
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
-10.5
-8
-6
-14
-8
-9
February
-10.8
-7
-11
-10
-9
-8
March
-5.7
-2
-3
-4
-4
-3
April
1.7
2
2
3
1
May
6.9
7
8
7
7
June
12.2
12
12
14
13
July
16.1
18
16
15
17
August
15.6
15
17
17
15
September
11.5
13
11
13
10
October
6.1
9
5
7
5
November
-2.6
-2
1
-1
1
December
-7.5
-4
-3
-7
-4
Average
2.2
-6.4
4.2
3.6
4.0
3.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
19.4
18
23
25
14
17
February
15.3
9
13
23
13
18
March
15.2
30
21
16
7
10
April
14.6
11
19
13
16
May
9.5
8
9
8
6
June
10.1
24
9
3
6
July
6.2
8
4
13
5
August
5.6
10
7
5
5
September
6.8
10
11
8
2
October
10.5
11
9
6
10
November
14.4
11
14
9
13
December
17.5
20
25
20
16
Average
12.4
19.7
14.0
12.9
9.5
9.5
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
7.6
8
8
8
8
6
February
8.0
9
7
9
7
7
March
9.4
9
9
9
10
9
April
9.0
8
10
10
10
May
8.5
10
8
8
10
June
7.0
6
7
8
7
July
6.7
6
8
7
7
August
6.3
7
7
6
6
September
6.9
6
7
7
9
October
7.0
6
6
6
8
November
7.3
7
8
6
7
December
7.3
7
11
6
9
Average
7.7
9.0
7.2
7.8
7.4
7.9
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
327°
336°
334°
335°
321°
February
292°
331°
291°
320°
292°
March
322°
333°
290°
275°
320°
April
235°
319°
339°
316°
May
311°
188°
293°
269°
June
069°
203°
210°
197°
July
184°
224°
321°
195°
August
223°
198°
192°
235°
September
326°
305°
232°
210°
October
230°
182°
341°
254°
November
281°
270°
288°
253°
December
329°
337°
307°
268°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.