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
83.9
75
76
87
90
92
February
86.6
97
89
84
80
82
March
88.8
85
88
83
95
90
April
93.0
90
93
92
97
May
94.3
99
92
94
97
June
94.0
88
95
97
95
July
93.1
87
98
87
96
August
95.1
92
98
96
95
September
91.2
86
88
97
95
October
88.2
89
91
87
84
November
91.7
95
91
96
94
December
81.2
71
85
79
87
Average
90.2
85.6
87.8
91.1
91.2
92.6
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
1.2
2
4
-1
-2
4
February
3.8
7
5
3
-1
4
March
7.8
10
8
9
9
11
April
14.6
18
15
14
13
May
21.4
22
24
19
21
June
26.0
25
26
26
28
July
28.7
30
30
24
30
August
27.0
26
30
26
26
September
23.3
24
23
23
21
October
17.2
19
17
18
15
November
8.9
9
12
9
11
December
3.8
7
4
6
3
Average
14.2
6.0
16.3
16.2
14.4
15.5
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
-4
-2
-11
-7
-4
February
-5.1
-3
-5
-7
-8
-4
March
-2.5
1
-1
-2
-2
1
April
4.2
6
4
3
4
May
10.0
8
12
8
10
June
14.8
15
15
15
16
July
18.4
19
19
16
19
August
17.2
17
19
17
16
September
13.2
14
13
13
11
October
7.8
9
6
10
5
November
0.3
0
3
0
1
December
-3.0
0
-2
-1
-4
Average
4.9
-2.1
6.8
6.0
5.2
5.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
21.2
29
31
18
16
14
February
18.9
9
20
20
33
20
March
16.6
19
21
19
8
14
April
17.4
15
19
18
22
May
11.9
7
7
13
5
June
8.2
11
8
6
4
July
8.0
10
7
16
3
August
6.3
9
4
8
6
September
8.4
13
15
4
6
October
12.5
15
8
11
15
November
13.3
7
13
12
12
December
20.1
29
18
14
18
Average
13.6
18.7
14.8
12.1
12.7
10.8
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
7.7
7
6
8
8
8
February
8.7
9
8
10
7
8
March
9.2
8
8
9
11
8
April
8.9
8
9
8
10
May
7.2
7
7
7
9
June
6.7
6
8
7
6
July
5.8
6
7
6
6
August
6.0
7
6
6
6
September
5.7
5
6
7
7
October
6.6
6
5
5
7
November
8.0
8
8
7
9
December
7.3
6
8
8
8
Average
7.3
7.8
6.5
7.5
7.1
7.6
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
265°
285°
264°
280°
270°
February
256°
244°
227°
268°
275°
March
278°
285°
253°
258°
243°
April
233°
266°
288°
284°
May
271°
168°
267°
257°
June
299°
240°
195°
227°
July
194°
235°
264°
220°
August
213°
217°
193°
245°
September
308°
250°
207°
186°
October
234°
201°
268°
201°
November
242°
229°
249°
222°
December
258°
283°
242°
243°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.