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
91.7
92
90
91
92
99
February
87.9
88
92
92
82
90
March
88.6
86
80
90
98
88
April
92.8
92
92
95
93
May
92.9
97
97
90
97
June
98.6
97
99
99
99
July
99.8
100
100
100
100
August
98.1
95
99
97
100
September
96.0
94
98
99
97
October
89.0
84
95
92
83
November
94.5
95
97
99
94
December
95.3
98
93
87
96
Average
93.1
88.4
92.9
95.5
94.6
94.8
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
3.7
1
3
5
4
5
February
1.7
6
4
4
-4
6
March
6.2
7
1
10
11
7
April
11.7
13
9
13
13
May
17.0
21
16
17
17
June
23.6
21
23
28
24
July
29.6
29
31
33
29
August
28.9
27
31
28
30
September
24.1
23
26
26
25
October
13.3
13
17
15
13
November
8.2
11
4
12
10
December
5.1
8
2
4
6
Average
11.7
4.7
14.3
15.2
15.5
15.2
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
-5.2
-8
-5
-5
-3
-4
February
-9.8
-3
-6
-8
-12
-5
March
-4.0
-3
-7
-2
-2
-3
April
-1.9
1
-3
0
0
May
5.1
8
4
4
6
June
10.3
10
9
12
10
July
13.8
13
14
16
13
August
13.5
15
15
13
13
September
9.3
10
10
9
9
October
2.6
3
5
5
2
November
-2.8
1
-5
2
0
December
-4.3
-1
-9
-6
-2
Average
0.8
-5.2
3.4
2.6
3.2
3.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
0.0
0
0
0
0
0
February
0.0
0
0
0
0
0
March
0.0
0
0
0
0
0
April
0.0
0
0
0
0
May
0.0
0
0
0
0
June
0.0
0
0
0
0
July
0.0
0
0
0
0
August
0.0
0
0
0
0
September
0.0
0
0
0
0
October
0.0
0
0
0
0
November
0.0
0
0
0
0
December
0.0
0
0
0
0
Average
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
17.8
13
18
21
18
18
February
16.1
15
19
20
15
18
March
12.2
11
9
16
14
13
April
12.4
12
13
12
14
May
10.4
9
13
10
11
June
10.2
7
12
10
12
July
9.2
9
9
9
10
August
9.6
10
10
11
9
September
10.8
8
9
12
13
October
13.4
10
14
12
15
November
17.6
17
18
19
19
December
17.3
17
14
15
21
Average
13.6
13.0
11.5
13.7
12.6
13.9
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
262°
262°
263°
264°
264°
February
262°
267°
266°
265°
264°
March
259°
269°
264°
267°
265°
April
263°
267°
269°
274°
May
252°
271°
281°
262°
June
256°
264°
269°
264°
July
264°
257°
275°
267°
August
267°
267°
262°
268°
September
258°
263°
263°
266°
October
264°
266°
265°
267°
November
258°
258°
266°
261°
December
260°
259°
254°
259°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.