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
81.2
78
64
93
76
86
February
89.6
97
89
92
89
96
March
90.6
92
84
89
94
92
April
90.1
90
88
90
93
94
May
95.7
98
97
94
97
June
97.7
97
100
100
100
July
97.3
100
97
94
99
August
95.9
98
94
98
98
September
94.5
94
98
95
96
October
92.9
94
99
92
91
November
91.2
100
83
98
93
December
81.9
80
76
88
85
Average
91.8
89.5
91.2
93.3
92.9
94.3
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
-4.7
-3
-2
-5
-2
-3
February
-2.7
6
0
-4
-7
-1
March
6.0
9
3
5
11
8
April
12.7
15
13
10
14
14
May
21.7
24
22
22
20
June
28.0
29
28
31
28
July
29.0
29
29
30
30
August
27.2
29
27
29
28
September
23.9
26
25
25
22
October
14.3
15
17
18
11
November
5.8
9
7
7
9
December
0.6
5
-1
1
1
Average
12.8
6.8
14.9
13.8
15.0
13.9
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
-11.6
-8
-8
-16
-9
-9
February
-11.4
-4
-10
-15
-14
-10
March
-3.0
-2
-5
-4
-1
0
April
2.6
5
3
1
3
2
May
10.5
12
11
9
10
June
16.7
17
16
18
16
July
18.4
17
19
18
20
August
17.1
18
17
18
18
September
13.8
16
13
13
11
October
5.8
7
5
9
2
November
-3.9
-1
-2
-1
0
December
-7.1
-2
-8
-8
-7
Average
3.5
-3.6
5.1
3.5
4.7
4.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
8.7
2
15
7
9
11
February
10.5
4
10
13
12
4
March
10.0
9
14
9
10
10
April
13.1
12
17
19
10
8
May
6.5
5
7
4
7
June
3.0
1
3
2
3
July
3.0
1
3
3
2
August
3.2
1
3
4
3
September
5.1
4
3
4
4
October
6.9
6
3
4
11
November
7.4
1
18
4
6
December
12.9
7
22
11
8
Average
7.3
7.2
6.6
8.1
6.0
6.1
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
7.3
7
7
9
6
7
February
8.3
9
8
9
8
9
March
8.9
9
9
9
10
9
April
9.6
11
10
11
9
9
May
8.1
8
9
8
9
June
8.0
7
9
7
9
July
6.8
7
8
6
7
August
7.4
7
7
8
8
September
8.0
8
8
8
8
October
8.6
9
9
7
9
November
8.8
8
9
10
9
December
7.5
7
8
9
8
Average
8.2
9.0
7.9
8.7
8.0
8.3
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
272°
293°
258°
336°
272°
February
251°
243°
289°
267°
270°
March
324°
006°
318°
182°
267°
April
308°
283°
235°
317°
303°
May
133°
173°
201°
017°
June
095°
227°
240°
127°
July
279°
263°
189°
210°
August
166°
158°
208°
213°
September
145°
201°
209°
242°
October
300°
235°
109°
261°
November
239°
249°
255°
220°
December
211°
132°
242°
263°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.