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
78.1
78
69
72
80
74
February
84.5
81
69
80
91
87
March
92.3
95
91
88
91
92
April
96.0
89
94
98
99
May
96.2
92
95
97
98
June
97.0
94
96
98
97
July
91.3
82
97
98
74
August
95.0
95
98
96
96
September
91.3
80
88
98
97
October
88.3
80
85
86
90
November
82.8
90
80
78
81
December
80.8
71
91
83
83
Average
90.1
84.7
83.5
89.4
92.2
89.8
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
-4.1
-6
-1
-3
-3
-5
February
-5.6
-2
-2
-1
-7
0
March
2.7
4
1
5
4
1
April
8.5
9
6
10
8
May
17.8
23
13
16
18
June
20.7
24
20
23
19
July
22.1
24
24
25
16
August
22.6
24
26
23
19
September
16.5
18
20
16
17
October
8.6
10
14
7
6
November
-1.8
3
-4
2
0
December
-5.1
0
-11
-12
0
Average
7.7
-2.5
11.1
9.7
8.6
8.1
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
-12.8
-12
-7
-13
-10
-14
February
-14.4
-12
-9
-9
-17
-10
March
-9.4
-8
-12
-5
-5
-12
April
-3.1
-2
-4
-3
-5
May
3.7
5
2
2
3
June
7.7
8
8
9
8
July
9.6
11
12
10
8
August
9.2
10
10
10
8
September
4.7
5
5
6
5
October
-1.7
0
2
0
-2
November
-6.6
-2
-10
-3
-5
December
-11.7
-5
-17
-19
-6
Average
-3.5
-11.5
0.0
-2.9
-2.3
-2.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
35.7
42
49
37
36
31
February
25.7
26
52
28
17
17
March
16.0
19
21
22
13
16
April
11.4
27
19
5
9
May
10.6
9
28
12
7
June
9.9
8
17
5
12
July
8.3
8
7
6
14
August
7.8
6
10
9
13
September
9.0
9
8
15
7
October
11.6
12
23
10
10
November
29.0
18
36
34
31
December
26.6
31
29
27
21
Average
16.5
28.9
20.3
21.3
14.2
14.6
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
5
5
6
5
6
February
6.1
5
7
6
6
6
March
5.9
6
5
6
7
7
April
6.1
6
6
6
6
May
5.4
5
6
5
6
June
5.7
6
5
5
6
July
3.8
5
6
2
5
August
5.4
6
6
6
6
September
5.7
6
6
7
5
October
6.1
6
7
6
5
November
6.2
6
7
7
6
December
5.6
6
6
6
6
Average
5.5
5.3
5.6
5.9
5.6
5.8
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
147°
151°
154°
162°
154°
February
142°
150°
177°
175°
162°
March
152°
216°
173°
169°
205°
April
167°
139°
175°
177°
May
215°
156°
172°
169°
June
180°
132°
188°
173°
July
160°
174°
164°
157°
August
163°
171°
177°
169°
September
167°
167°
165°
177°
October
145°
169°
174°
143°
November
163°
140°
157°
153°
December
158°
150°
143°
159°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.