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
80.4
73
79
86
83
73
February
88.1
76
95
83
93
96
March
93.8
87
89
98
97
95
April
89.8
86
74
94
94
May
94.4
96
89
92
96
June
97.2
95
97
98
99
July
96.6
98
96
91
96
August
92.1
95
96
89
89
September
93.7
88
92
99
99
October
89.6
84
91
85
94
November
89.4
90
87
89
93
December
87.2
87
56
87
95
Average
90.2
79.1
90.6
88.2
91.7
93.6
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
-8.2
-7
-8
-11
-4
-7
February
-8.1
0
-7
-10
-11
-5
March
0.5
2
-5
-1
8
2
April
8.1
5
4
12
8
May
20.0
24
18
19
18
June
26.2
28
23
28
26
July
27.1
26
27
29
27
August
25.6
26
26
26
26
September
18.6
23
22
24
21
October
9.0
12
13
15
8
November
1.5
4
1
3
6
December
-4.1
2
-7
-7
0
Average
7.6
-2.4
10.8
7.9
11.9
10.8
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
-17.6
-14
-16
-22
-12
-15
February
-18.4
-8
-17
-22
-20
-14
March
-10.8
-9
-15
-9
-6
-7
April
-3.1
-4
-4
-3
-3
May
6.5
10
7
5
6
June
13.2
15
10
15
13
July
15.2
13
17
16
16
August
13.3
14
15
14
14
September
8.2
11
9
11
8
October
1.5
3
3
5
-1
November
-7.6
-5
-7
-5
-6
December
-13.3
-8
-15
-15
-10
Average
-3.8
-11.7
0.2
-3.6
0.3
0.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.5
13
11
12
6
9
February
6.7
5
4
11
6
2
March
4.1
9
5
4
2
3
April
7.5
14
17
2
8
May
3.4
3
6
2
2
June
1.8
3
0
1
1
July
0.9
1
1
1
2
August
1.7
1
1
2
2
September
2.9
3
3
1
1
October
5.9
10
3
8
4
November
7.8
5
13
6
2
December
9.7
6
31
11
3
Average
5.3
8.9
5.0
7.6
3.5
2.9
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
8.6
8
6
10
8
8
February
8.9
9
8
11
9
9
March
9.3
10
9
10
10
10
April
10.3
10
12
11
9
May
9.8
10
11
10
10
June
8.2
7
8
9
10
July
7.2
7
8
7
7
August
6.7
7
7
8
7
September
8.6
7
9
9
10
October
9.5
8
9
10
10
November
9.1
10
10
9
8
December
8.2
8
11
8
8
Average
8.8
9.1
8.1
9.5
8.8
8.8
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
293°
312°
314°
299°
244°
February
310°
294°
313°
275°
287°
March
336°
329°
319°
249°
308°
April
349°
354°
340°
308°
May
044°
293°
322°
016°
June
063°
346°
285°
178°
July
311°
299°
297°
244°
August
351°
318°
207°
300°
September
021°
327°
264°
294°
October
326°
314°
334°
289°
November
293°
296°
286°
274°
December
300°
327°
292°
299°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.