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
82.9
87
71
76
86
88
February
84.3
88
81
79
81
90
March
88.8
89
83
84
95
86
April
90.2
88
79
97
90
May
94.3
95
94
95
96
June
92.2
69
93
96
93
July
95.7
92
98
93
95
August
94.4
93
94
95
88
September
91.6
91
89
91
93
October
88.2
96
87
75
93
November
86.6
84
91
88
90
December
82.0
80
92
80
78
Average
89.5
88.1
86.1
88.0
90.2
90.6
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
-5.0
-4
-4
-9
-4
-3
February
-3.7
1
-3
-5
-3
-1
March
2.7
5
2
2
6
4
April
10.2
12
10
14
10
May
18.9
19
21
20
19
June
23.8
23
23
26
25
July
27.0
26
26
25
29
August
25.0
23
24
28
24
September
20.6
21
19
21
19
October
13.7
14
14
16
12
November
4.2
4
6
5
8
December
-2.1
-1
2
0
-1
Average
10.2
1.2
11.5
11.4
12.9
12.0
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
-14.9
-9
-10
-18
-10
-11
February
-13.5
-7
-12
-13
-15
-13
March
-8.9
-3
-6
-7
-7
-6
April
0.1
2
2
2
-1
May
6.6
8
12
6
5
June
12.4
16
15
13
12
July
15.8
18
18
15
17
August
14.8
15
17
17
14
September
10.0
11
11
10
9
October
4.8
6
5
7
3
November
-4.9
-3
0
-3
-1
December
-10.6
-7
-4
-8
-8
Average
0.8
-6.1
3.3
3.4
2.3
1.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
13.6
14
43
25
5
9
February
15.8
18
23
31
14
7
March
13.2
15
16
25
9
14
April
14.9
16
34
11
13
May
10.2
12
17
9
5
June
9.2
12
15
10
7
July
6.4
10
10
9
6
August
6.2
8
11
2
14
September
6.0
9
12
1
7
October
9.9
19
18
10
8
November
12.3
23
12
0
11
December
11.6
30
5
0
18
Average
11.7
15.4
17.1
18.4
6.7
9.6
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
5.7
6
5
6
5
5
February
6.2
7
7
7
5
6
March
7.3
8
8
7
8
5
April
7.0
7
8
6
7
May
5.8
7
4
5
7
June
5.4
6
7
4
5
July
3.8
5
6
2
0
August
4.1
6
6
3
2
September
5.1
5
6
6
4
October
5.3
7
6
5
5
November
6.7
7
7
6
6
December
5.8
7
7
6
7
Average
5.9
7.1
6.4
6.4
4.9
4.7
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
133°
345°
329°
319°
339°
February
360°
334°
355°
304°
297°
March
324°
322°
318°
309°
103°
April
198°
327°
321°
298°
May
347°
078°
321°
345°
June
339°
253°
270°
218°
July
280°
295°
087°
154°
August
317°
327°
281°
336°
September
319°
336°
296°
170°
October
287°
137°
053°
252°
November
242°
261°
258°
233°
December
295°
304°
199°
308°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.