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
91.9
88
85
89
96
98
February
86.9
86
86
86
87
94
March
85.5
80
67
85
98
91
April
89.2
83
88
94
93
May
94.5
97
96
93
96
June
97.7
96
98
99
99
July
99.3
97
100
100
100
August
97.1
94
97
96
100
September
96.2
95
97
99
97
October
91.5
81
92
92
91
November
92.8
97
87
100
97
December
89.5
95
77
84
93
Average
92.1
84.6
89.2
91.8
95.1
95.8
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
3.4
3
2
5
4
5
February
1.5
6
3
4
-4
4
March
7.5
8
2
10
11
8
April
12.2
12
9
13
13
May
18.5
21
17
18
18
June
24.2
22
24
29
24
July
30.6
30
32
34
30
August
29.6
28
32
28
31
September
24.0
24
27
26
26
October
14.2
14
17
16
14
November
7.7
11
3
11
10
December
4.1
8
-1
4
6
Average
13.7
5.2
14.8
15.3
16.0
15.7
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
-6.0
-9
-7
-4
-4
-3
February
-9.8
-3
-6
-8
-11
-5
March
-4.1
-3
-8
-3
-2
-3
April
-1.1
-1
-4
-1
-1
May
4.7
7
4
3
5
June
8.3
9
8
9
8
July
11.1
9
12
13
10
August
10.8
12
12
11
11
September
6.9
8
8
6
6
October
1.7
2
4
4
0
November
-2.2
0
-7
1
0
December
-5.2
-2
-7
-6
-3
Average
0.7
-6.9
2.1
1.6
2.0
2.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.9
14
17
13
7
4
February
15.9
17
19
15
18
9
March
13.3
17
30
13
4
10
April
14.0
19
16
11
10
May
10.9
7
23
7
11
June
7.8
14
6
1
9
July
1.7
2
4
2
1
August
3.0
6
2
5
1
September
5.2
7
2
1
3
October
11.7
20
12
9
14
November
9.3
7
20
2
1
December
10.3
6
26
13
7
Average
9.9
16.2
13.0
11.9
6.2
6.7
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
17.2
15
16
21
17
18
February
16.9
16
20
20
15
18
March
12.9
11
10
16
15
15
April
12.7
13
14
13
13
May
10.8
10
12
10
12
June
9.7
8
10
9
11
July
8.0
8
8
9
9
August
9.3
10
10
11
9
September
11.1
10
9
13
13
October
14.1
10
12
14
15
November
17.8
18
17
21
20
December
18.0
16
17
20
18
Average
12.9
13.5
12.0
13.4
13.4
13.7
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
244°
243°
233°
231°
232°
February
242°
237°
234°
230°
241°
March
246°
279°
239°
241°
243°
April
252°
256°
245°
257°
May
066°
252°
301°
237°
June
018°
261°
287°
259°
July
315°
277°
288°
278°
August
261°
277°
247°
285°
September
240°
278°
248°
251°
October
256°
262°
228°
247°
November
239°
251°
235°
236°
December
249°
237°
223°
239°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.