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
73.3
58
80
61
91
89
February
89.9
95
97
99
86
100
March
98.0
99
100
100
100
98
April
99.0
100
99
96
100
100
May
99.4
100
100
100
99
June
99.9
100
100
100
99
July
99.9
100
100
100
100
August
92.7
90
97
78
100
September
90.2
99
96
86
74
October
99.2
97
100
99
100
November
89.9
89
85
88
92
December
76.3
81
56
91
74
Average
92.4
87.9
94.4
92.1
93.5
94.1
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
4.3
2
5
1
6
7
February
7.4
9
8
9
7
12
March
13.3
15
11
15
14
14
April
17.8
18
16
14
21
20
May
24.6
27
20
24
24
June
28.2
29
26
32
27
July
33.6
34
34
36
32
August
32.7
32
35
31
32
September
26.1
25
28
26
28
October
18.3
18
22
17
19
November
9.2
9
6
11
10
December
4.0
6
-1
4
5
Average
17.5
11.0
18.4
18.1
19.1
19.2
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
-4.7
-4
-3
-6
-1
-2
February
-4.5
0
-4
-4
-3
-3
March
-1.4
-1
-1
1
-1
-1
April
3.1
3
2
1
3
3
May
8.7
11
6
7
8
June
11.8
12
11
15
12
July
14.7
15
15
18
14
August
14.1
15
14
14
14
September
9.0
9
10
8
10
October
3.2
4
6
4
3
November
-2.4
-1
-4
2
-2
December
-3.4
1
-8
-3
-3
Average
3.9
-1.5
5.0
3.7
5.3
4.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
10.3
21
10
4
7
7
February
9.2
8
4
4
10
1
March
3.7
4
3
4
0
4
April
4.8
3
7
11
3
2
May
3.6
2
11
1
4
June
2.1
1
3
1
4
July
0.4
1
1
0
0
August
1.1
5
1
0
0
September
2.4
3
1
5
1
October
4.1
4
5
4
4
November
6.0
6
8
5
7
December
8.0
14
19
5
4
Average
4.8
9.0
4.7
5.6
3.0
2.9
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
3.1
3
3
2
3
4
February
4.6
4
5
4
6
5
March
5.5
6
5
5
6
6
April
5.9
5
5
7
6
6
May
5.9
6
6
6
7
June
5.7
5
5
5
7
July
4.8
4
5
5
5
August
4.8
5
5
5
5
September
4.4
5
5
4
4
October
4.4
4
4
5
6
November
3.7
3
4
5
4
December
2.8
3
3
5
2
Average
4.7
4.6
4.4
4.7
5.1
5.1
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
285°
286°
258°
237°
247°
February
224°
284°
315°
277°
259°
March
245°
258°
269°
244°
250°
April
274°
228°
277°
332°
296°
May
293°
272°
287°
292°
June
293°
260°
287°
292°
July
256°
263°
294°
283°
August
281°
255°
292°
251°
September
253°
287°
233°
203°
October
283°
244°
221°
268°
November
265°
269°
210°
241°
December
255°
273°
237°
242°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.