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
82.7
87
82
82
94
85
February
85.4
89
80
79
89
87
March
79.0
69
72
70
88
85
April
84.7
85
76
95
92
May
89.6
95
80
88
98
June
81.8
71
82
77
93
July
79.1
47
79
88
81
August
84.8
70
85
84
95
September
80.2
74
61
78
93
October
80.8
76
74
80
80
November
83.8
79
82
86
84
December
86.4
93
73
93
76
Average
83.0
80.3
75.1
76.8
86.2
88.3
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
-8.7
-6
-6
-11
-4
-8
February
-7.5
-3
-8
-9
-4
-5
March
-1.0
1
1
-2
0
-2
April
4.3
5
5
8
4
May
11.6
13
12
11
15
June
17.2
18
18
18
18
July
21.2
22
21
20
21
August
20.3
19
22
21
21
September
15.4
19
15
16
14
October
9.3
12
11
12
7
November
1.0
1
1
4
2
December
-4.5
-1
-1
-4
-2
Average
5.7
-3.3
7.8
7.1
8.3
7.1
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
-18.1
-16
-16
-23
-12
-18
February
-19.6
-14
-23
-20
-15
-16
March
-11.3
-6
-8
-13
-10
-14
April
-4.7
-3
-2
0
-3
May
1.6
2
1
2
2
June
7.7
9
9
8
8
July
11.8
14
11
11
13
August
11.3
11
12
12
11
September
6.1
8
7
8
4
October
1.5
4
3
3
0
November
-7.8
-8
-6
-2
-7
December
-12.3
-10
-7
-12
-9
Average
-4.4
-12.0
-2.7
-3.9
-1.5
-3.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
38.4
36
27
41
33
38
February
35.5
32
37
42
25
30
March
33.6
41
40
41
25
26
April
22.0
20
28
19
15
May
17.4
17
25
21
11
June
16.1
27
23
17
9
July
12.3
17
14
12
17
August
14.8
31
10
12
15
September
18.0
21
16
28
14
October
20.1
25
22
26
22
November
28.7
30
34
22
26
December
29.7
19
40
26
44
Average
23.9
36.7
25.5
25.8
21.2
20.1
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
8
7
February
8.5
8
8
8
8
8
March
9.5
9
9
10
10
9
April
9.5
10
10
8
10
May
9.1
9
9
9
9
June
8.3
8
9
8
8
July
7.6
7
8
7
7
August
7.4
8
7
7
8
September
7.6
7
8
8
8
October
8.1
8
9
7
8
November
8.4
9
8
8
7
December
8.5
8
10
9
8
Average
8.4
8.6
8.1
8.6
8.0
8.3
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
331°
358°
328°
359°
351°
February
359°
326°
330°
321°
302°
March
061°
080°
359°
327°
012°
April
093°
045°
056°
275°
May
330°
062°
356°
329°
June
107°
099°
136°
137°
July
114°
187°
179°
133°
August
094°
177°
155°
253°
September
096°
037°
078°
224°
October
047°
150°
090°
336°
November
329°
358°
296°
332°
December
323°
045°
321°
006°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.