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
76.7
72
54
78
88
76
February
87.9
68
90
83
93
96
March
88.9
92
84
85
90
95
April
94.4
90
91
100
95
May
97.0
95
97
98
97
June
94.5
87
93
99
98
July
94.3
91
94
91
97
August
94.2
86
96
98
98
September
94.7
84
97
99
98
October
92.7
91
93
93
97
November
81.7
83
78
88
71
December
88.9
93
71
87
95
Average
89.9
77.4
85.4
89.2
94.1
93.4
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
-9.7
-11
-9
-6
-6
-9
February
-9.0
-4
-7
-9
-14
-5
March
-2.2
-4
-6
-1
4
-2
April
8.8
8
7
13
6
May
19.7
23
19
19
18
June
23.5
26
22
26
21
July
25.7
25
26
29
25
August
25.0
26
27
26
25
September
19.8
23
24
22
19
October
10.3
11
15
12
7
November
-3.9
4
-5
0
-2
December
-7.2
1
-14
-13
-5
Average
7.0
-7.7
10.4
9.5
9.8
8.2
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
-18.5
-19
-16
-20
-15
-19
February
-19.0
-13
-17
-20
-23
-17
March
-12.2
-14
-16
-11
-7
-13
April
-4.1
-3
-4
-3
-7
May
4.6
8
4
3
4
June
9.9
11
9
11
10
July
11.8
11
13
13
12
August
10.7
11
12
11
11
September
5.8
6
7
6
5
October
-2.2
-1
0
-1
-3
November
-9.0
-6
-13
-3
-10
December
-16.5
-9
-22
-21
-13
Average
-5.6
-16.7
-2.3
-3.0
-3.8
-4.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
20.1
23
28
25
22
16
February
20.1
32
22
29
11
12
March
12.5
14
21
17
11
11
April
9.9
17
18
2
9
May
5.3
5
7
4
4
June
7.7
5
11
4
16
July
4.7
6
7
1
7
August
4.1
9
5
7
3
September
5.6
4
2
3
4
October
6.2
17
1
3
4
November
18.7
4
31
13
25
December
13.7
2
34
22
14
Average
11.2
22.8
11.6
14.2
7.5
9.8
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
8.2
8
7
8
9
9
February
8.6
8
9
10
10
8
March
9.9
10
8
12
10
10
April
10.9
11
13
9
11
May
10.0
10
11
10
11
June
9.3
9
9
9
10
July
8.4
8
8
9
9
August
8.6
8
8
8
10
September
9.4
8
10
10
11
October
9.7
10
9
10
11
November
9.2
9
10
9
9
December
7.5
6
9
9
7
Average
9.2
8.8
8.7
9.8
9.3
9.7
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
023°
057°
007°
275°
339°
February
030°
300°
006°
292°
281°
March
101°
112°
356°
225°
338°
April
091°
018°
310°
308°
May
111°
336°
189°
144°
June
170°
358°
266°
009°
July
322°
328°
328°
264°
August
304°
284°
315°
258°
September
226°
264°
264°
288°
October
032°
284°
128°
289°
November
257°
334°
069°
326°
December
253°
054°
277°
280°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.