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
93.4
93
93
94
94
95
February
90.3
93
96
93
75
90
March
94.1
96
96
93
91
April
95.3
95
96
95
May
92.0
95
93
88
92
June
98.1
94
99
100
100
July
96.6
99
98
92
97
August
98.8
100
99
98
100
September
97.2
96
97
98
98
October
93.6
94
100
96
90
November
92.9
97
94
95
99
December
93.8
97
91
95
95
Average
94.3
94.1
96.0
95.8
93.9
95.4
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
4.0
3
1
5
6
6
February
4.2
9
4
5
-5
5
March
10.5
12
8
11
11
April
16.2
16
16
17
May
20.3
22
20
20
20
June
28.0
25
29
30
30
July
31.8
30
33
32
32
August
31.1
31
33
31
33
September
27.0
26
29
29
25
October
16.0
17
18
18
13
November
11.2
12
8
14
14
December
6.6
9
3
10
6
Average
15.9
7.9
16.8
17.7
19.3
18.2
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
-7.4
-9
-7
-7
-5
-5
February
-8.8
-3
-6
-8
-14
-6
March
-3.0
-2
-4
-4
-1
April
0.0
1
-1
0
May
7.3
9
6
8
7
June
13.1
12
13
15
13
July
16.3
15
18
17
16
August
15.2
15
17
14
16
September
11.0
12
12
12
9
October
1.9
3
4
4
0
November
-2.0
-1
-6
1
-1
December
-5.3
-3
-8
-4
-5
Average
2.4
-5.1
3.9
3.2
5.3
4.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.1
11
15
12
7
8
February
19.2
12
11
14
49
21
March
10.6
13
10
13
7
April
6.7
7
6
8
May
7.0
9
7
6
5
June
3.0
6
1
2
3
July
1.9
2
2
2
2
August
1.4
2
1
3
1
September
1.5
1
1
2
3
October
5.6
4
1
5
7
November
6.4
7
7
3
2
December
7.7
4
14
6
8
Average
7.2
11.7
6.2
6.0
6.7
5.4
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
11.4
9
9
13
14
13
February
12.0
11
13
14
9
13
March
12.5
11
14
12
13
April
13.2
12
17
11
May
10.7
10
11
10
11
June
9.0
8
9
9
10
July
8.6
7
9
8
10
August
8.6
9
9
8
9
September
9.1
9
9
9
9
October
10.8
9
11
11
12
November
11.3
10
12
12
11
December
12.1
14
13
13
11
Average
10.5
10.2
10.3
11.4
10.1
10.8
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
294°
316°
297°
310°
293°
February
286°
308°
302°
264°
305°
March
266°
316°
318°
288°
April
333°
304°
308°
May
158°
278°
177°
208°
June
128°
298°
174°
295°
July
296°
155°
136°
180°
August
257°
242°
254°
185°
September
313°
310°
303°
304°
October
314°
336°
314°
269°
November
289°
320°
295°
284°
December
289°
311°
272°
305°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.