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
81.2
75
79
75
92
85
February
87.1
89
82
81
81
91
March
91.8
93
94
89
92
85
April
92.6
96
85
93
97
May
90.9
74
88
99
99
June
93.4
90
95
95
89
July
90.7
84
98
83
97
August
91.7
85
94
98
94
September
94.8
85
95
100
97
October
91.0
80
95
83
96
November
85.8
81
83
90
89
December
85.7
97
69
73
87
Average
89.9
85.3
85.1
88.2
90.5
92.7
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
-7.4
-11
-5
-6
-3
-11
February
-7.3
-3
-4
-5
-11
-3
March
0.9
1
-2
3
5
-2
April
7.5
11
7
7
6
May
17.2
22
14
16
16
June
20.7
23
20
23
19
July
22.4
23
23
24
22
August
22.0
22
25
23
23
September
16.7
19
20
17
17
October
9.0
10
14
10
6
November
-1.4
4
-2
2
-1
December
-6.9
-1
-12
-13
-3
Average
6.7
-5.9
10.3
9.1
8.2
7.3
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
-15.0
-18
-12
-17
-12
-19
February
-17.6
-12
-14
-15
-20
-14
March
-11.4
-10
-13
-8
-8
-14
April
-4.9
-1
-3
-3
-5
May
4.4
7
3
5
4
June
10.2
11
10
12
9
July
12.3
13
13
13
13
August
11.0
12
12
11
11
September
6.1
7
8
7
7
October
0.1
1
3
0
-1
November
-9.9
-4
-10
-8
-9
December
-15.6
-10
-21
-20
-11
Average
-4.7
-14.5
-1.7
-2.6
-2.0
-3.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
26.5
39
20
39
19
17
February
29.5
26
42
40
28
18
March
20.5
21
29
32
12
29
April
13.7
11
26
12
11
May
11.4
14
27
13
8
June
11.0
15
12
5
18
July
8.5
13
7
5
10
August
7.7
16
12
8
4
September
8.2
4
9
5
9
October
12.7
17
10
6
22
November
25.8
13
45
15
24
December
23.0
8
44
39
17
Average
16.6
28.6
16.7
23.8
12.9
14.8
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
8.4
8
8
9
10
8
February
8.2
8
8
9
10
9
March
7.9
9
7
10
8
8
April
7.7
8
9
6
9
May
7.5
7
8
8
7
June
7.6
7
7
9
8
July
7.4
7
8
8
8
August
7.8
7
7
8
11
September
7.9
7
8
9
9
October
8.9
9
10
8
10
November
8.2
8
9
8
8
December
8.0
6
8
9
7
Average
7.9
8.2
7.3
8.4
8.3
8.4
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°
324°
289°
243°
093°
February
287°
305°
300°
283°
286°
March
105°
091°
305°
315°
294°
April
110°
292°
308°
292°
May
103°
295°
021°
327°
June
323°
320°
286°
292°
July
284°
287°
275°
287°
August
283°
265°
282°
269°
September
268°
278°
281°
281°
October
261°
267°
216°
278°
November
286°
300°
309°
272°
December
113°
293°
284°
292°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.