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
83.1
67
78
99
79
89
February
90.6
80
89
97
94
96
March
77.9
85
83
91
88
73
April
93.4
94
97
98
96
95
May
89.1
86
93
91
89
June
97.7
97
97
100
99
July
95.0
97
92
91
97
August
93.7
94
92
97
96
September
93.3
86
97
95
99
October
90.4
83
98
92
95
November
91.1
87
92
97
96
December
86.4
79
72
95
91
Average
89.6
82.1
88.3
93.8
93.0
93.0
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
2.2
-1
0
6
3
3
February
3.9
11
3
7
-3
6
March
10.9
12
8
12
14
12
April
17.3
18
19
18
18
17
May
21.9
24
23
21
20
June
29.5
28
31
31
31
July
30.3
30
31
30
31
August
29.7
31
32
30
31
September
27.2
28
30
29
26
October
17.2
17
21
20
16
November
11.7
13
10
15
15
December
5.6
8
4
9
7
Average
16.4
10.0
17.4
19.1
18.0
17.8
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
-9.8
-11
-8
-10
-5
-7
February
-9.4
-3
-8
-10
-14
-7
March
-3.5
-3
-4
-4
-1
0
April
1.6
4
1
2
1
0
May
9.2
10
9
10
9
June
15.7
15
16
16
17
July
17.6
16
18
18
18
August
16.0
17
16
17
16
September
12.1
12
11
12
10
October
2.9
4
3
5
2
November
-4.9
-3
-6
-1
-2
December
-7.6
-4
-8
-6
-6
Average
3.0
-4.6
4.0
3.5
4.3
4.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
8.1
14
15
5
5
8
February
7.2
8
10
4
8
7
March
6.8
3
4
9
11
8
April
6.1
7
3
4
6
7
May
6.9
4
8
3
8
June
2.5
3
3
2
2
July
2.5
4
6
2
1
August
2.1
3
1
1
1
September
2.8
2
2
4
4
October
5.7
6
1
3
3
November
5.1
12
3
3
3
December
9.2
17
18
2
5
Average
5.5
7.7
6.4
4.9
4.1
4.5
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
10.0
10
9
12
11
9
February
10.4
11
10
13
8
11
March
11.6
12
12
13
12
12
April
13.6
13
15
17
12
13
May
10.2
10
10
10
10
June
9.6
7
10
9
12
July
6.9
6
8
8
5
August
7.6
7
8
8
8
September
8.9
8
8
9
9
October
10.5
10
11
10
11
November
10.5
9
12
10
11
December
10.3
10
13
10
10
Average
10.1
11.5
9.4
11.0
9.7
10.0
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
314°
333°
294°
311°
295°
February
292°
311°
312°
296°
312°
March
340°
336°
340°
328°
259°
April
318°
307°
294°
327°
315°
May
121°
301°
128°
039°
June
130°
162°
168°
150°
July
104°
143°
150°
145°
August
206°
140°
154°
162°
September
160°
142°
175°
261°
October
325°
286°
296°
307°
November
280°
315°
287°
250°
December
311°
309°
307°
320°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.