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
80.1
81
78
86
81
80
February
82.1
94
82
76
82
76
March
87.1
81
84
90
94
92
April
92.4
94
96
88
91
May
95.8
97
96
96
97
June
95.7
89
96
100
94
July
95.6
92
98
94
August
95.1
96
94
95
September
92.5
89
88
96
October
92.5
95
95
89
November
86.3
91
91
93
December
81.4
75
83
85
87
Average
89.8
84.9
89.3
91.6
91.9
90.3
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
-4.9
-2
0
-5
-4
-2
February
-1.2
2
0
-1
-3
-2
March
2.9
5
3
4
5
5
April
10.2
14
11
12
8
May
18.0
18
21
18
17
June
22.1
22
22
25
19
July
24.9
26
26
23
August
24.0
23
25
26
September
20.1
22
19
20
October
14.3
15
16
15
November
4.2
5
8
5
December
-1.6
2
2
1
3
Average
9.6
1.4
12.4
12.6
12.1
6.4
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
-12.8
-8
-6
-18
-10
-9
February
-11.5
-7
-11
-12
-12
-11
March
-6.0
-3
-5
-5
-6
-4
April
0.5
2
1
1
-1
May
6.0
5
7
6
6
June
11.1
12
11
14
9
July
14.6
17
14
14
August
13.7
14
14
16
September
10.3
11
10
11
October
5.3
7
4
7
November
-4.7
-3
0
-2
December
-8.0
-4
-5
-7
-5
Average
0.2
-7.9
3.4
1.9
2.6
-4.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
25.3
31
25
19
23
28
February
21.6
11
20
27
20
30
March
18.6
24
24
17
15
15
April
18.2
14
18
20
20
May
10.6
6
11
9
7
June
9.2
15
10
2
4
July
9.6
16
4
15
August
7.2
10
7
9
September
8.0
7
11
7
October
14.5
17
8
19
November
22.0
14
20
18
December
27.6
24
29
24
29
Average
16.0
21.6
15.3
13.6
14.2
16.2
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
5
5
6
5
5
February
6.5
6
6
8
6
6
March
6.9
6
7
7
7
7
April
6.9
7
7
7
7
May
5.6
7
6
6
5
June
5.4
5
7
7
6
July
4.5
4
5
4
August
4.6
5
4
4
September
4.3
3
4
6
October
5.3
5
5
4
November
5.4
5
6
5
December
5.1
4
7
6
8
Average
5.7
5.6
5.3
5.8
5.4
6.3
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
255°
292°
287°
300°
241°
February
251°
240°
226°
258°
245°
March
276°
284°
245°
248°
238°
April
208°
280°
316°
279°
May
300°
239°
285°
288°
June
360°
243°
231°
266°
July
210°
236°
271°
August
231°
254°
215°
September
293°
267°
219°
October
206°
191°
251°
November
231°
220°
238°
December
216°
267°
242°
193°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.