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
76.0
62
71
90
85
67
February
86.8
92
87
95
84
93
March
85.8
93
81
89
91
78
April
91.2
88
92
89
98
94
May
89.8
91
90
89
90
June
95.2
91
93
99
96
July
96.3
94
95
96
98
August
95.2
92
95
99
98
September
92.2
90
90
97
89
October
90.7
91
100
92
93
November
90.7
99
86
97
90
December
83.7
79
64
90
85
Average
89.2
83.4
88.2
90.6
93.2
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
-2.8
-2
0
-2
0
-1
February
2.0
11
4
2
-6
2
March
9.2
13
8
10
13
11
April
16.0
18
17
14
17
16
May
22.5
25
23
21
20
June
29.0
29
29
31
29
July
29.4
29
30
29
30
August
28.1
29
29
29
29
September
25.7
28
25
28
23
October
16.7
18
19
19
15
November
8.9
12
9
11
13
December
4.0
7
2
7
3
Average
15.0
9.8
17.1
16.2
16.6
15.6
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
-10.4
-9
-8
-15
-8
-8
February
-9.2
-3
-7
-11
-14
-7
March
-2.7
0
-3
-1
1
1
April
3.7
6
3
2
5
3
May
10.9
11
12
10
10
June
16.9
16
17
17
18
July
18.1
17
18
18
19
August
16.7
18
17
18
17
September
13.1
14
11
13
11
October
5.3
8
3
9
3
November
-2.0
-1
-2
-1
0
December
-6.3
-2
-6
-4
-8
Average
3.9
-2.3
5.6
4.1
5.4
4.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.0
17
8
7
5
12
February
8.6
1
14
8
10
6
March
8.5
7
14
10
5
7
April
7.5
7
6
9
3
7
May
5.4
2
6
7
7
June
3.4
3
5
3
3
July
1.9
3
2
2
3
August
3.4
5
4
1
1
September
5.0
4
1
1
11
October
7.1
6
4
8
3
November
5.9
2
15
2
5
December
7.8
9
18
2
7
Average
6.2
8.2
6.3
6.6
3.8
5.9
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
9.2
9
9
10
8
9
February
9.8
10
10
12
9
10
March
10.7
12
11
11
11
10
April
11.8
13
13
14
11
11
May
9.1
9
10
10
9
June
8.0
7
8
8
9
July
6.5
6
7
6
6
August
6.8
7
6
7
8
September
7.8
7
7
8
9
October
9.5
10
8
9
10
November
10.3
9
12
11
11
December
9.3
9
10
10
9
Average
9.2
11.1
8.7
9.3
8.8
9.1
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
308°
300°
304°
334°
302°
February
273°
306°
315°
329°
316°
March
345°
328°
324°
153°
288°
April
305°
280°
240°
275°
293°
May
130°
187°
171°
020°
June
124°
205°
214°
171°
July
296°
219°
212°
146°
August
165°
196°
163°
177°
September
176°
190°
187°
238°
October
295°
266°
316°
292°
November
248°
274°
265°
235°
December
269°
204°
249°
285°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.