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
78.3
67
65
68
90
84
February
81.5
60
91
75
84
94
March
80.5
80
66
74
86
88
April
84.1
71
71
94
88
May
91.5
76
93
88
98
June
93.5
92
91
96
91
July
94.2
87
89
94
98
August
95.7
94
93
96
100
September
91.8
89
96
96
95
October
89.2
83
77
94
96
November
73.8
82
48
94
76
December
85.5
89
64
87
86
Average
86.0
69.5
81.2
78.5
91.9
91.9
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
-5.5
-7
-3
-5
-3
-6
February
-7.5
0
-4
-5
-11
-1
March
1.7
1
-4
3
8
3
April
9.6
8
8
12
8
May
19.3
23
18
17
18
June
23.8
25
23
26
22
July
27.5
27
28
31
25
August
27.0
28
30
25
28
September
21.2
24
25
24
21
October
10.9
10
14
15
8
November
1.2
4
-3
5
3
December
-4.8
5
-11
-8
-1
Average
9.2
-3.6
11.9
11.2
11.7
10.6
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
-13.0
-16
-10
-15
-10
-14
February
-16.3
-10
-12
-16
-20
-11
March
-9.6
-9
-13
-8
-4
-8
April
-3.4
-3
-4
-2
-4
May
5.2
9
5
3
4
June
10.3
12
10
12
10
July
12.5
12
13
15
12
August
11.7
13
13
12
11
September
7.3
9
9
8
7
October
-1.3
0
2
1
-3
November
-7.0
-5
-10
-5
-7
December
-12.2
-5
-20
-18
-9
Average
-3.8
-12.4
0.5
-1.0
-1.4
-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
20.3
27
26
31
22
12
February
24.9
30
23
31
20
13
March
24.8
33
50
33
11
17
April
18.2
40
33
12
13
May
7.8
15
16
8
2
June
5.5
6
9
3
8
July
4.0
4
10
4
5
August
3.9
4
5
7
0
September
5.2
7
2
3
3
October
9.7
18
10
3
10
November
25.1
20
48
11
18
December
20.6
6
54
17
19
Average
14.6
30.0
19.3
22.7
9.4
9.3
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
12.9
11
12
16
14
13
February
12.4
11
13
14
14
13
March
12.6
12
12
15
13
13
April
12.7
12
14
12
13
May
11.6
11
13
12
13
June
11.6
10
12
12
12
July
10.1
11
10
10
11
August
10.1
10
10
10
11
September
11.4
10
12
13
13
October
12.5
12
12
12
12
November
13.0
11
14
14
16
December
12.5
12
12
13
13
Average
11.8
11.5
11.3
12.8
12.1
12.6
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
262°
265°
268°
237°
255°
February
270°
262°
270°
267°
245°
March
223°
182°
284°
242°
257°
April
100°
310°
295°
295°
May
094°
277°
239°
207°
June
204°
275°
273°
265°
July
311°
283°
162°
248°
August
296°
264°
266°
243°
September
245°
237°
260°
275°
October
278°
277°
238°
271°
November
248°
280°
243°
254°
December
246°
263°
253°
257°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.