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
78.5
81
69
73
86
72
February
92.8
82
95
87
97
98
March
90.8
93
91
88
93
93
April
96.5
95
96
98
97
May
94.8
86
96
98
96
June
95.2
93
96
96
94
July
94.8
97
92
94
97
August
93.0
84
95
94
95
September
92.3
88
94
98
99
October
94.1
89
99
90
97
November
84.5
83
81
86
80
December
89.1
100
90
86
92
Average
91.3
85.9
89.0
91.3
93.5
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
-10.3
-11
-9
-11
-7
-10
February
-10.4
-3
-8
-12
-14
-6
March
-2.1
-2
-6
-2
3
-2
April
7.6
7
5
12
5
May
19.1
23
18
18
18
June
23.1
27
22
26
20
July
24.8
24
25
28
25
August
24.0
23
26
24
25
September
19.1
22
22
22
18
October
9.3
9
13
12
6
November
-3.4
2
-4
0
-2
December
-9.8
-1
-14
-14
-5
Average
6.3
-6.5
9.4
8.1
9.2
7.6
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
-20.3
-19
-17
-23
-17
-19
February
-22.4
-13
-21
-25
-25
-19
March
-15.9
-14
-21
-14
-9
-15
April
-6.9
-6
-4
-3
-8
May
3.7
6
4
2
4
June
10.0
12
9
11
11
July
11.9
10
12
14
14
August
10.1
11
12
11
11
September
5.2
7
6
7
4
October
-2.1
-1
0
-1
-2
November
-11.4
-6
-12
-10
-12
December
-18.4
-12
-22
-22
-15
Average
-6.5
-16.4
-4.8
-5.9
-4.4
-4.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
40.4
47
40
46
32
36
February
29.9
38
23
43
27
22
March
18.3
18
18
24
9
19
April
11.8
16
20
6
11
May
8.2
9
9
4
9
June
10.4
2
14
8
22
July
6.2
9
8
2
6
August
7.7
18
7
12
4
September
7.7
2
7
2
7
October
13.2
24
4
7
21
November
36.8
20
50
21
31
December
28.0
4
43
43
24
Average
18.4
33.6
14.5
19.9
12.2
16.3
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
7.2
8
6
8
7
7
February
7.9
10
8
7
8
8
March
8.2
9
7
9
8
8
April
9.5
10
10
10
9
May
9.5
11
10
10
9
June
8.9
11
8
9
9
July
7.7
9
7
8
8
August
7.8
9
7
7
9
September
8.5
10
8
9
9
October
9.0
10
9
8
10
November
8.3
11
9
7
8
December
7.2
9
8
8
6
Average
8.4
8.8
9.4
8.4
8.2
8.5
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
203°
321°
332°
257°
316°
February
180°
293°
320°
287°
283°
March
150°
132°
331°
187°
329°
April
141°
059°
333°
296°
May
144°
042°
111°
153°
June
177°
020°
281°
039°
July
194°
287°
318°
264°
August
184°
293°
323°
266°
September
191°
272°
279°
301°
October
188°
293°
078°
296°
November
220°
356°
004°
332°
December
213°
002°
293°
273°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.