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
75.0
70
61
82
73
80
February
84.0
78
93
69
92
91
March
89.7
78
82
89
97
95
April
87.6
82
74
84
92
May
91.8
92
88
92
96
June
95.7
94
90
99
96
July
95.4
97
92
95
98
August
91.0
89
91
72
97
September
79.4
91
88
12
97
October
87.7
83
93
80
95
November
78.9
70
70
73
88
December
73.7
57
62
78
71
Average
85.9
75.4
84.0
83.9
79.5
92.6
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
-8.3
-5
-6
-11
-5
-7
February
-7.9
2
-3
-10
-10
-5
March
2.1
3
0
1
8
3
April
8.4
8
6
11
8
May
18.8
24
18
19
17
June
24.7
27
24
27
24
July
26.5
25
26
28
27
August
24.5
25
26
22
26
September
17.2
23
21
3
18
October
10.8
13
14
14
7
November
1.2
5
3
3
4
December
-5.9
3
-5
-4
-3
Average
8.5
0.0
12.0
9.9
9.8
9.8
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
-17.4
-12
-13
-23
-14
-15
February
-18.4
-7
-16
-23
-22
-18
March
-9.1
-6
-12
-9
-5
-9
April
-2.1
-2
-2
-1
-3
May
6.0
10
7
6
5
June
12.4
15
11
13
13
July
14.0
13
14
14
15
August
12.7
15
15
11
13
September
8.2
13
10
1
7
October
2.4
5
4
4
-1
November
-7.8
-2
-5
-5
-6
December
-13.8
-3
-13
-14
-12
Average
-2.3
-9.4
2.0
-1.2
-1.1
-1.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
13.0
15
12
17
10
16
February
13.9
12
6
32
4
7
March
9.2
22
18
9
4
4
April
11.4
16
31
12
3
May
5.8
5
12
3
5
June
4.7
6
5
2
6
July
3.3
3
6
1
1
August
3.1
3
6
0
3
September
6.6
8
9
0
6
October
10.9
14
9
5
10
November
16.1
14
32
9
6
December
15.8
14
33
18
13
Average
9.5
16.5
9.5
15.3
5.0
5.8
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
7.2
7
6
8
7
7
February
8.1
9
8
10
7
7
March
8.8
11
9
9
9
8
April
9.3
10
11
9
9
May
8.8
9
10
9
9
June
7.7
7
6
7
10
July
7.1
7
7
7
7
August
7.2
7
7
7
8
September
7.4
7
8
1
9
October
8.6
8
9
7
9
November
8.2
7
9
7
9
December
7.3
7
8
7
7
Average
8.1
8.7
7.6
8.4
7.0
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
259°
278°
275°
263°
244°
February
298°
274°
299°
265°
276°
March
329°
349°
314°
200°
264°
April
013°
033°
345°
318°
May
104°
209°
274°
308°
June
093°
280°
274°
199°
July
299°
287°
265°
245°
August
325°
254°
222°
242°
September
106°
262°
157°
273°
October
307°
263°
181°
265°
November
263°
286°
250°
249°
December
267°
104°
256°
270°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.