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
79.3
65
76
91
82
77
February
87.3
97
90
86
83
91
March
91.4
91
93
91
96
86
April
92.4
94
97
94
94
91
May
93.2
97
89
97
91
June
94.4
87
99
98
100
July
97.8
94
96
98
99
August
98.8
97
98
100
99
September
96.0
94
97
100
92
October
90.8
94
92
89
94
November
92.9
94
94
98
93
December
87.8
78
74
91
95
Average
91.8
87.3
91.5
92.8
94.4
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
1.1
0
3
-1
2
3
February
4.3
10
6
3
-2
3
March
9.5
13
8
11
13
10
April
15.6
17
18
14
17
15
May
22.0
23
24
21
21
June
27.9
27
30
29
29
July
29.3
29
30
28
31
August
28.5
28
29
30
29
September
25.5
25
26
27
24
October
17.8
18
19
20
16
November
9.4
11
12
9
14
December
5.4
8
4
8
5
Average
15.6
10.0
17.0
17.1
16.8
16.5
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
-5.1
-4
-2
-9
-3
-3
February
-4.0
1
-3
-6
-9
-5
March
1.2
3
1
2
3
2
April
6.0
8
6
6
7
5
May
12.2
12
15
12
11
June
18.2
17
19
20
19
July
21.0
20
22
21
22
August
20.1
20
21
22
20
September
16.8
17
17
17
15
October
9.4
10
9
13
7
November
1.9
3
3
1
5
December
-2.8
3
-2
1
-2
Average
7.3
1.8
8.7
8.5
8.7
8.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
22.7
27
29
16
23
20
February
15.5
2
13
22
23
18
March
12.7
9
20
25
6
11
April
12.4
14
9
15
8
14
May
8.7
7
14
9
9
June
5.2
4
4
8
3
July
3.7
7
5
4
3
August
3.0
5
5
1
1
September
5.5
10
4
2
8
October
11.0
15
7
11
9
November
11.2
10
17
8
9
December
13.8
22
24
7
10
Average
10.3
13.1
11.7
12.2
8.6
9.0
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
9.6
9
9
11
9
9
February
10.3
9
11
11
9
11
March
10.9
11
11
11
11
10
April
10.7
12
11
12
10
10
May
9.5
8
11
10
9
June
9.0
9
9
9
9
July
8.2
8
9
8
8
August
8.2
9
9
8
8
September
8.6
8
8
9
10
October
9.6
10
10
9
10
November
9.9
9
11
10
11
December
9.5
9
10
10
9
Average
9.6
10.5
9.1
9.9
9.3
9.4
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
271°
264°
282°
279°
245°
February
257°
254°
266°
283°
296°
March
274°
310°
264°
209°
247°
April
253°
239°
212°
241°
299°
May
057°
149°
136°
067°
June
034°
248°
223°
178°
July
276°
267°
327°
224°
August
338°
241°
176°
193°
September
138°
295°
238°
254°
October
267°
242°
337°
267°
November
250°
233°
248°
234°
December
251°
203°
234°
254°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.