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
64.7
65
69
39
64
70
February
68.5
96
51
40
64
91
March
91.4
92
91
85
94
100
April
73.3
94
93
12
87
May
86.6
96
84
77
86
June
91.0
90
83
92
99
July
94.0
94
87
96
97
August
95.1
97
90
97
98
September
86.5
93
72
89
84
October
87.6
92
92
82
89
November
89.7
94
87
97
87
December
80.5
73
80
72
90
Average
85.2
85.1
87.6
79.1
78.7
89.6
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
0.3
-1
2
1
1
2
February
3.1
10
3
2
2
3
March
9.2
12
7
10
12
9
April
11.7
17
13
2
13
May
17.0
23
23
0
20
June
24.4
27
28
13
28
July
28.9
28
28
27
30
August
28.1
28
27
30
29
September
24.4
24
23
26
23
October
16.4
17
17
19
15
November
8.4
10
10
9
13
December
4.6
6
3
5
4
Average
13.7
6.5
16.0
15.9
12.1
16.7
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
-6.9
-6
-3
-4
-5
-4
February
-5.7
-1
-3
-2
-8
-4
March
0.1
2
0
1
2
0
April
3.4
6
4
0
3
May
7.9
11
10
0
10
June
13.4
15
11
8
16
July
18.0
18
12
19
20
August
17.2
17
13
20
18
September
13.1
15
7
12
13
October
6.8
8
6
10
4
November
0.4
1
2
0
4
December
-2.2
1
-2
-1
-3
Average
4.9
-2.3
7.3
5.1
4.8
7.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
0.0
0
0
0
0
0
February
0.0
0
0
0
0
0
March
0.0
0
0
0
0
0
April
0.0
0
0
0
0
May
0.0
0
0
0
0
June
0.0
0
0
0
0
July
0.0
0
0
0
0
August
0.0
0
0
0
0
September
0.0
0
0
0
0
October
0.0
0
0
0
0
November
0.0
0
0
0
0
December
0.0
0
0
0
0
Average
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
5.5
7
6
4
4
6
February
5.3
7
4
4
5
7
March
7.3
9
8
7
7
7
April
6.1
8
8
1
7
May
5.7
6
7
6
6
June
4.7
5
5
4
5
July
4.0
5
5
2
4
August
4.0
6
5
2
4
September
4.3
5
5
3
5
October
5.6
7
6
4
6
November
6.1
7
7
6
7
December
5.5
7
7
5
4
Average
5.5
7.8
6.0
5.8
3.9
5.3
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
256°
253°
235°
298°
241°
February
246°
245°
221°
289°
310°
March
256°
253°
254°
202°
230°
April
226°
195°
019°
303°
May
059°
156°
182°
086°
June
052°
254°
210°
159°
July
258°
253°
278°
196°
August
270°
240°
204°
218°
September
155°
276°
243°
228°
October
255°
233°
016°
254°
November
243°
231°
237°
224°
December
246°
205°
219°
246°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.