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
80.6
75
77
87
80
81
February
83.7
94
82
91
86
71
March
88.1
95
65
97
94
85
April
87.2
63
94
97
91
May
92.3
89
93
95
97
June
94.8
89
99
96
97
July
94.4
93
95
94
97
August
95.8
98
95
93
97
September
92.6
92
94
93
95
October
89.6
89
94
88
85
November
89.9
95
75
92
93
December
84.3
85
72
86
86
Average
89.3
88.1
84.8
91.8
92.0
90.2
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
2.0
1
4
-1
2
5
February
4.8
9
9
3
0
3
March
10.3
12
9
12
14
11
April
14.9
17
14
17
14
May
21.3
21
23
21
18
June
26.4
25
27
28
27
July
28.2
27
27
29
30
August
27.0
25
26
30
27
September
24.4
23
22
27
24
October
18.2
17
17
20
17
November
9.8
11
11
9
13
December
5.1
7
4
8
4
Average
14.3
7.1
16.2
15.8
17.5
15.3
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
-5.9
-4
-1
-9
-2
-1
February
-4.7
-2
-2
-6
-7
-3
March
0.6
2
-1
1
1
3
April
4.6
4
4
5
4
May
10.2
9
12
9
8
June
16.4
14
15
18
17
July
19.1
18
18
20
20
August
16.7
16
16
20
15
September
13.9
13
13
16
12
October
8.0
8
5
11
7
November
0.8
1
1
0
3
December
-2.4
1
-2
0
-2
Average
5.4
-2.2
6.5
5.9
8.0
6.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
17.7
26
16
13
18
16
February
13.2
6
4
19
16
18
March
9.6
9
9
9
5
13
April
9.5
6
12
9
14
May
8.6
7
8
9
12
June
5.1
5
3
7
7
July
4.3
3
7
4
5
August
3.2
4
2
4
3
September
5.1
4
3
6
2
October
7.0
8
2
8
10
November
7.6
8
7
7
12
December
10.5
10
5
11
11
Average
9.1
13.6
6.7
7.1
8.1
9.5
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
7.2
8
7
7
6
7
February
7.4
8
9
7
6
7
March
8.3
9
10
8
8
8
April
7.9
8
7
7
9
May
6.7
6
7
6
9
June
5.7
6
4
6
5
July
4.4
5
4
5
4
August
4.4
5
5
4
4
September
5.1
4
5
5
5
October
6.0
6
8
5
5
November
7.1
7
8
6
8
December
6.5
6
7
6
7
Average
6.6
7.9
6.4
6.2
5.9
6.4
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
239°
232°
262°
262°
219°
February
264°
230°
229°
298°
271°
March
247°
258°
240°
242°
246°
April
233°
230°
250°
266°
May
017°
177°
290°
241°
June
353°
261°
220°
305°
July
244°
247°
276°
275°
August
267°
243°
232°
280°
September
045°
278°
247°
200°
October
258°
234°
210°
234°
November
231°
220°
229°
238°
December
223°
211°
209°
233°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.