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
78.9
69
52
93
80
86
February
87.1
70
88
92
93
95
March
78.8
85
40
91
89
90
April
83.5
32
94
88
94
97
May
92.0
88
97
94
94
June
96.3
97
93
100
100
July
94.5
92
94
88
99
August
95.1
94
96
98
96
September
91.6
85
98
96
99
October
84.8
87
63
83
89
November
80.7
79
75
37
100
December
81.8
74
57
89
90
Average
85.4
62.9
80.6
87.8
87.8
94.8
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
1.0
-3
-1
4
4
1
February
2.5
9
2
6
-3
5
March
9.3
11
4
10
14
12
April
15.4
16
16
15
16
16
May
21.8
25
22
22
20
June
29.3
29
28
32
30
July
32.3
31
34
33
32
August
30.6
32
33
33
31
September
26.8
29
30
28
26
October
16.3
16
20
19
15
November
11.0
13
8
13
14
December
4.2
7
0
5
7
Average
15.7
8.0
16.9
18.0
18.0
17.4
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
-9.7
-11
-8
-9
-4
-8
February
-9.4
-2
-8
-10
-13
-6
March
-3.5
-3
-6
-4
1
0
April
1.8
4
2
1
2
1
May
9.4
11
9
9
8
June
16.2
16
16
16
18
July
18.5
17
19
19
19
August
17.2
18
18
18
18
September
13.1
14
13
14
11
October
4.3
4
6
7
3
November
-2.6
-1
-4
0
1
December
-6.0
-3
-10
-6
-5
Average
3.6
-3.0
4.7
4.1
5.3
5.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.5
18
23
9
10
6
February
9.0
9
8
10
8
2
March
9.2
6
16
8
12
5
April
10.7
17
7
22
8
7
May
8.0
5
4
7
10
June
2.4
2
3
1
2
July
2.0
3
2
5
1
August
2.1
4
1
1
1
September
5.5
5
3
7
10
October
9.2
13
9
3
8
November
5.9
4
10
7
1
December
10.8
14
25
7
5
Average
7.5
12.4
8.1
8.2
5.9
4.8
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
10.5
11
9
12
11
10
February
10.9
10
12
13
10
10
March
12.1
12
12
14
13
13
April
12.8
10
14
17
13
13
May
10.4
9
11
10
11
June
9.8
8
10
10
11
July
9.2
8
10
10
10
August
9.2
10
10
10
9
September
9.9
9
11
10
11
October
11.9
12
12
12
12
November
10.9
10
12
11
11
December
11.4
11
16
11
11
Average
10.7
10.5
10.2
11.9
10.9
10.9
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
283°
294°
289°
282°
243°
February
301°
252°
301°
277°
286°
March
326°
328°
318°
294°
280°
April
338°
310°
305°
311°
296°
May
148°
260°
133°
173°
June
191°
179°
186°
169°
July
166°
166°
153°
167°
August
220°
170°
170°
165°
September
179°
215°
213°
283°
October
315°
289°
275°
285°
November
284°
293°
288°
245°
December
289°
299°
270°
290°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.