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
79.7
67
82
91
78
77
February
87.7
95
89
92
86
91
March
90.7
94
90
94
91
81
April
92.5
98
97
94
89
May
93.5
98
92
96
94
June
95.0
92
98
96
98
July
95.8
94
95
90
96
August
95.8
96
94
97
98
September
92.9
91
95
100
87
October
90.0
93
87
85
96
November
92.2
97
95
98
94
December
85.7
77
80
84
93
Average
90.9
86.2
91.8
93.0
91.7
91.5
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
0.5
-1
3
-2
0
2
February
4.0
11
7
3
-4
2
March
10.2
13
9
11
13
11
April
16.1
18
14
17
15
May
22.8
25
24
21
21
June
28.1
28
28
29
29
July
28.8
29
28
28
30
August
27.9
28
28
29
28
September
25.8
25
25
27
23
October
17.6
18
18
19
17
November
9.1
11
11
9
13
December
5.3
7
4
8
4
Average
15.2
7.5
17.2
16.2
16.4
16.3
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
-7.2
-6
-3
-12
-5
-5
February
-6.2
-2
-4
-8
-12
-6
March
0.2
2
0
0
2
1
April
4.4
4
4
5
4
May
11.5
11
13
11
11
June
16.6
13
18
18
17
July
18.4
17
19
19
19
August
17.0
17
17
18
17
September
14.0
14
13
14
13
October
6.9
8
4
11
5
November
-1.7
0
1
0
3
December
-3.0
1
-3
-2
-4
Average
5.1
-2.0
6.5
5.7
6.6
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
8.9
11
2
3
15
9
February
8.7
3
3
7
8
18
March
8.1
9
6
4
8
15
April
8.7
4
4
11
10
May
7.1
2
4
14
9
June
2.7
1
2
3
2
July
2.2
1
3
2
4
August
1.9
3
1
1
1
September
4.2
8
2
0
6
October
7.5
6
4
7
9
November
5.9
3
3
2
5
December
7.0
13
7
2
5
Average
6.1
7.5
4.2
3.4
6.0
7.5
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
6.8
6
6
8
6
6
February
7.5
7
8
8
7
7
March
8.1
9
8
8
8
7
April
8.3
9
10
8
8
May
6.5
6
8
6
7
June
5.4
4
6
5
6
July
4.1
3
5
4
3
August
4.1
4
4
4
3
September
4.7
4
5
6
4
October
6.3
6
7
6
5
November
7.2
6
8
8
8
December
6.6
6
7
8
6
Average
6.4
7.3
5.6
6.8
6.1
5.8
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
258°
247°
277°
271°
250°
February
257°
254°
249°
298°
292°
March
259°
280°
266°
192°
248°
April
248°
216°
252°
280°
May
037°
173°
187°
182°
June
019°
255°
226°
198°
July
274°
243°
251°
222°
August
257°
226°
195°
221°
September
176°
272°
235°
232°
October
275°
242°
248°
262°
November
251°
231°
244°
224°
December
256°
196°
232°
259°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.