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
84.3
71
87
78
95
84
February
89.5
89
86
95
84
March
91.5
90
92
90
86
98
April
97.8
98
97
96
96
May
99.3
98
100
99
100
June
97.8
99
95
96
99
July
93.7
94
56
99
97
August
90.7
52
86
94
81
September
94.9
93
94
100
October
93.9
90
81
99
99
November
85.4
86
78
87
52
December
83.5
84
83
85
83
Average
92.0
83.9
90.4
87.9
94.3
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
0.3
-1
4
-1
3
-4
February
1.3
1
1
3
2
March
4.3
6
3
5
3
4
April
9.8
9
9
9
9
May
14.7
14
15
13
17
June
17.4
16
20
17
16
July
18.8
19
17
19
19
August
18.1
19
17
17
19
September
14.6
14
14
14
October
9.1
9
11
8
8
November
3.3
6
2
3
1
December
1.6
4
-2
-3
2
Average
8.4
2.0
8.7
9.3
9.4
8.4
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
-4.2
-6
0
-5
-1
-8
February
-4.3
-3
-3
-2
-2
March
-2.0
-2
-3
1
-2
-3
April
2.1
2
1
1
2
May
6.7
7
5
6
7
June
10.1
10
10
9
10
July
12.0
12
13
11
12
August
11.6
13
12
12
14
September
8.6
10
9
9
October
4.3
4
7
4
4
November
-1.4
1
-1
-1
-2
December
-3.5
0
-6
-9
0
Average
2.6
-4.4
3.2
3.5
3.6
2.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
26.3
40
27
24
14
31
February
20.2
13
21
28
35
March
16.4
23
15
21
21
13
April
11.5
17
14
11
13
May
10.2
11
11
14
5
June
11.6
11
11
13
17
July
9.3
6
35
4
14
August
15.1
28
12
14
28
September
18.7
22
25
7
October
22.0
30
32
25
16
November
20.3
19
31
22
17
December
26.4
34
16
21
40
Average
17.0
24.8
17.9
19.9
15.8
16.9
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
12.5
11
11
12
10
16
February
13.2
12
12
19
14
March
10.7
9
11
9
10
14
April
9.8
9
9
10
11
May
9.8
10
8
11
9
June
8.9
10
7
7
9
July
8.0
6
6
8
9
August
8.3
3
7
10
6
September
7.7
10
9
7
October
8.6
6
10
8
12
November
8.9
9
10
9
5
December
9.9
11
12
10
11
Average
9.7
10.6
9.0
9.4
9.1
10.7
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
035°
086°
063°
199°
041°
February
051°
159°
197°
199°
March
166°
047°
202°
197°
052°
April
205°
134°
191°
203°
May
208°
206°
207°
209°
June
207°
211°
212°
208°
July
217°
211°
212°
209°
August
224°
210°
210°
216°
September
209°
210°
214°
October
115°
210°
207°
204°
November
193°
058°
040°
038°
December
200°
176°
039°
101°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.