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
88.6
82
75
96
90
94
February
91.0
81
88
98
94
93
March
87.1
90
77
88
93
79
April
95.5
95
99
100
96
96
May
89.2
88
94
88
90
June
97.2
93
99
98
100
July
94.3
85
95
98
96
August
95.8
98
97
98
99
September
95.8
94
95
97
98
October
92.3
88
99
95
95
November
92.2
93
95
94
97
December
90.8
85
76
100
94
Average
92.1
87.4
88.6
94.8
94.9
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
4.4
2
-1
6
5
7
February
5.8
12
3
8
-1
9
March
12.5
14
8
13
14
13
April
18.4
20
19
19
18
18
May
22.7
23
25
22
22
June
30.7
26
32
32
34
July
32.6
31
34
33
33
August
31.7
33
34
33
33
September
28.7
30
29
30
28
October
18.6
19
21
21
18
November
13.0
14
11
16
16
December
7.5
9
5
11
8
Average
18.0
11.7
17.9
20.1
19.6
19.9
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
-8.0
-10
-9
-9
-7
-7
February
-8.0
-3
-8
-9
-12
-7
March
-3.6
-2
-4
-3
-1
-1
April
1.7
3
1
2
1
0
May
8.5
10
8
9
9
June
15.0
14
15
16
16
July
17.1
14
19
17
18
August
15.8
17
16
17
17
September
11.7
12
12
12
10
October
2.5
4
4
4
1
November
-3.2
-3
-6
-1
-2
December
-7.8
-4
-9
-6
-6
Average
2.9
-4.9
3.7
3.6
4.2
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
4.9
7
11
6
4
1
February
6.4
4
8
2
7
7
March
6.8
6
8
15
3
6
April
4.1
6
0
1
6
5
May
3.9
4
4
5
1
June
2.2
4
1
1
2
July
0.7
1
1
1
1
August
1.0
1
1
1
1
September
2.2
2
5
2
2
October
4.0
3
1
1
2
November
3.1
7
4
1
1
December
6.0
15
3
1
6
Average
3.8
5.4
4.9
3.5
2.6
2.7
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
9.8
10
9
10
10
10
February
10.3
11
10
12
9
12
March
11.2
11
11
12
11
11
April
13.0
14
13
17
12
12
May
10.6
10
12
11
10
June
9.7
9
11
9
12
July
7.6
7
8
9
5
August
8.0
9
8
8
9
September
8.5
8
9
8
9
October
10.2
10
10
10
10
November
9.8
9
11
10
10
December
10.5
11
12
9
11
Average
10.1
11.4
9.5
10.9
9.6
9.9
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
331°
335°
310°
326°
320°
February
316°
315°
317°
023°
328°
March
007°
001°
348°
360°
318°
April
322°
322°
314°
340°
328°
May
123°
247°
126°
086°
June
143°
187°
141°
149°
July
107°
158°
145°
133°
August
190°
163°
156°
152°
September
156°
112°
293°
316°
October
328°
313°
332°
331°
November
322°
323°
309°
268°
December
322°
310°
304°
316°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.