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
94.2
93
90
97
67
97
February
87.5
90
94
96
100
93
March
88.9
93
89
88
96
79
April
94.1
92
96
100
92
95
May
89.1
93
92
100
93
June
97.5
99
99
100
99
July
94.3
96
95
97
94
August
96.1
98
97
97
98
September
93.2
95
93
98
97
October
94.8
96
100
99
94
November
93.8
97
100
98
December
95.1
95
89
99
95
Average
93.8
91.9
95.1
94.7
98.5
93.9
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
4.2
4
-1
6
-3
7
February
6.1
11
3
6
4
7
March
11.2
12
7
13
7
13
April
16.6
19
17
16
12
18
May
20.5
22
23
14
22
June
28.0
25
30
24
32
July
30.6
29
33
33
32
August
29.7
31
31
32
32
September
25.9
28
26
28
25
October
17.2
18
19
20
17
November
12.8
13
15
14
December
6.8
8
3
10
6
Average
16.9
11.2
16.7
19.6
17.0
18.8
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
-9.4
-10
-10
-10
-4
-7
February
-8.2
-4
-14
-10
1
-8
March
-4.1
-3
-14
-5
2
-2
April
-1.8
1
-1
-3
6
-2
May
6.1
8
4
9
6
June
10.6
12
7
15
9
July
13.3
14
11
18
15
August
11.4
14
11
13
15
September
8.0
5
3
12
10
October
1.1
2
7
2
0
November
-4.8
-3
-2
-3
December
-7.1
-5
-11
-7
-7
Average
1.2
-5.9
0.7
0.6
4.2
2.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
5.1
5
10
6
33
2
February
8.5
5
5
5
0
8
March
6.3
4
4
12
0
5
April
4.0
7
2
0
8
3
May
5.7
5
5
0
2
June
1.6
6
2
0
3
July
0.4
1
0
0
1
August
0.8
1
0
1
0
September
1.6
2
2
1
3
October
3.6
1
4
0
4
November
2.7
6
3
2
December
4.0
6
8
1
6
Average
3.5
5.4
3.4
3.7
1.0
3.0
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
8.8
8
9
10
10
10
February
9.0
9
10
10
6
11
March
10.6
9
11
11
11
10
April
11.9
12
11
16
8
10
May
9.5
9
11
10
11
June
8.9
8
10
9
10
July
7.8
7
8
6
9
August
7.6
8
7
7
8
September
7.4
7
7
8
9
October
9.2
8
7
10
10
November
9.2
8
9
9
December
9.8
10
13
10
10
Average
9.1
9.8
8.5
9.7
8.9
9.7
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
315°
281°
295°
360°
294°
February
300°
264°
297°
296°
315°
March
347°
340°
328°
320°
291°
April
320°
303°
305°
278°
320°
May
122°
208°
082°
085°
June
142°
172°
350°
236°
July
087°
130°
107°
133°
August
270°
132°
103°
125°
September
303°
095°
326°
329°
October
317°
325°
289°
318°
November
310°
299°
253°
December
303°
287°
246°
301°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.