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
85.2
86
91
82
85
87
February
83.1
94
69
79
89
86
March
90.9
83
94
94
87
85
April
94.7
91
95
96
92
May
99.1
96
100
100
99
June
98.3
97
97
100
99
July
94.9
91
92
99
95
August
95.8
94
97
93
98
September
94.9
97
91
91
98
October
87.4
71
89
88
87
November
84.5
74
89
81
88
December
82.2
73
59
86
87
Average
91.8
86.9
88.2
91.2
92.7
92.9
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
-6.8
-7
-1
-3
-2
-13
February
-4.9
-2
-2
1
-6
-3
March
1.0
2
2
5
-3
-1
April
8.8
7
10
9
8
May
15.4
15
17
16
17
June
19.6
18
23
20
19
July
21.1
21
21
20
21
August
18.8
21
17
18
20
September
13.9
13
14
13
14
October
7.1
7
7
6
6
November
-2.7
2
-2
-9
-2
December
-4.8
-4
-8
-6
-2
Average
6.6
-3.9
8.1
9.2
6.4
7.0
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
-12.3
-13
-7
-9
-7
-20
February
-11.7
-9
-10
-5
-13
-11
March
-8.7
-5
-7
-3
-13
-10
April
-1.1
-2
-1
-3
-1
May
5.0
6
5
5
5
June
9.4
9
11
9
9
July
11.4
12
11
11
11
August
10.2
13
11
9
10
September
6.2
6
7
4
6
October
0.5
0
0
0
-1
November
-8.4
-4
-7
-14
-9
December
-10.2
-12
-14
-13
-8
Average
-2.6
-10.9
0.4
1.0
-2.0
-2.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.2
16
6
20
10
9
February
19.0
10
33
27
19
21
March
8.5
6
10
6
13
14
April
5.9
11
5
8
5
May
4.5
6
2
5
5
June
5.7
8
1
3
10
July
9.0
11
17
7
10
August
15.9
16
30
19
9
September
13.4
17
26
8
11
October
13.5
17
7
21
12
November
11.2
28
11
9
11
December
18.4
24
34
17
17
Average
10.5
10.1
14.2
13.8
10.7
10.4
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
5.4
6
5
7
6
3
February
5.2
10
4
5
5
5
March
6.0
5
5
8
4
6
April
6.1
5
5
6
5
May
7.1
8
6
6
7
June
5.0
6
4
5
5
July
4.4
4
5
4
5
August
4.6
5
5
4
5
September
4.9
4
5
4
6
October
5.3
3
5
5
5
November
5.7
6
6
2
8
December
5.1
4
2
5
7
Average
5.5
6.7
5.0
5.2
4.8
5.4
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
360°
002°
057°
003°
022°
February
037°
355°
025°
357°
058°
March
065°
053°
030°
323°
023°
April
163°
108°
156°
326°
May
135°
138°
138°
134°
June
134°
171°
148°
138°
July
143°
127°
151°
143°
August
123°
070°
114°
116°
September
063°
085°
087°
090°
October
348°
090°
049°
058°
November
003°
006°
040°
011°
December
002°
358°
007°
018°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.