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
83.9
78
74
98
82
85
February
88.9
83
90
94
93
91
March
82.4
86
78
95
85
78
April
90.2
90
96
95
91
92
May
88.5
90
97
92
88
June
96.5
96
95
100
98
July
95.6
97
96
91
99
August
94.7
97
92
95
98
September
92.1
90
97
94
97
October
89.5
83
98
91
92
November
92.3
94
95
99
98
December
84.8
81
65
91
91
Average
89.6
84.5
89.3
94.1
92.1
92.4
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
1.7
-2
-1
5
3
3
February
2.6
9
2
6
-3
6
March
9.2
11
6
11
13
11
April
15.0
16
16
15
15
16
May
20.5
23
21
20
19
June
27.9
27
29
30
29
July
30.3
29
33
30
30
August
28.8
30
32
29
31
September
25.7
27
28
27
26
October
15.8
16
19
18
15
November
10.7
13
8
14
14
December
4.3
7
0
7
7
Average
15.1
8.3
16.2
17.7
17.0
17.1
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
-9.3
-11
-9
-10
-5
-7
February
-10.9
-3
-8
-10
-14
-6
March
-4.9
-3
-6
-4
-1
-1
April
1.1
3
1
0
1
1
May
8.3
10
8
8
8
June
14.5
14
15
15
16
July
17.2
16
17
17
19
August
15.7
16
17
15
17
September
12.1
12
12
13
11
October
2.9
3
4
5
2
November
-3.5
-2
-6
0
-1
December
-7.6
-4
-10
-7
-6
Average
2.6
-4.4
3.7
3.1
4.0
4.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
7.1
7
8
3
11
8
February
10.1
7
2
7
15
5
March
6.1
3
6
1
9
7
April
5.9
7
2
6
9
5
May
6.7
3
3
3
7
June
1.9
1
1
2
1
July
1.5
3
1
1
1
August
1.5
3
1
1
1
September
2.1
1
1
5
1
October
3.6
4
2
0
4
November
3.6
4
2
3
2
December
9.4
11
16
6
4
Average
4.9
5.8
3.7
2.9
5.1
3.5
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
9.4
9
8
13
10
9
February
10.0
10
11
12
8
11
March
11.0
11
10
13
12
12
April
12.6
13
14
16
13
12
May
9.8
9
10
9
10
June
9.1
7
10
9
11
July
7.8
6
9
8
9
August
7.9
8
9
8
8
September
8.7
8
9
8
10
October
10.5
10
10
10
10
November
10.1
10
11
10
10
December
10.0
9
11
10
10
Average
9.8
10.7
9.1
10.8
9.5
10.1
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
300°
304°
297°
300°
276°
February
293°
283°
309°
283°
301°
March
328°
316°
333°
299°
287°
April
326°
322°
305°
327°
310°
May
176°
280°
130°
105°
June
186°
202°
203°
176°
July
182°
198°
163°
164°
August
233°
189°
178°
180°
September
189°
212°
224°
273°
October
316°
298°
293°
304°
November
296°
303°
296°
255°
December
304°
301°
287°
312°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.