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
73.1
64
49
92
68
82
February
87.6
92
89
89
88
94
March
87.5
91
81
83
94
81
April
87.7
85
82
86
95
91
May
89.8
92
92
92
87
June
92.2
86
92
92
88
July
94.3
95
91
94
97
August
92.5
94
85
91
97
September
90.7
87
90
97
95
October
90.9
85
93
93
94
November
88.6
97
73
97
91
December
78.6
77
66
82
95
Average
87.9
83.1
84.7
86.9
90.9
90.8
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
-4.8
-3
-2
-6
-2
-1
February
-1.7
8
1
-3
-6
0
March
5.8
9
4
4
10
7
April
12.5
14
14
10
15
12
May
20.7
23
22
20
18
June
26.4
28
26
29
26
July
28.3
28
28
28
29
August
26.5
28
26
27
27
September
22.5
24
22
24
20
October
14.2
15
16
18
11
November
5.9
8
8
7
11
December
0.3
4
0
1
0
Average
12.5
7.0
14.5
13.2
14.2
13.2
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
-11.6
-8
-7
-16
-8
-8
February
-11.3
-5
-9
-13
-15
-12
March
-4.0
-3
-5
-4
-1
-1
April
1.3
3
2
1
3
0
May
8.1
8
10
8
7
June
14.0
14
14
16
13
July
16.0
15
16
16
18
August
14.9
15
14
16
15
September
11.8
14
11
11
10
October
4.7
6
4
8
2
November
-3.2
-2
-2
-3
0
December
-7.1
-2
-6
-7
-7
Average
2.2
-4.8
4.0
2.6
3.7
3.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.6
17
17
10
6
9
February
9.8
4
17
14
8
6
March
9.8
12
14
15
8
13
April
13.3
22
20
19
5
6
May
8.9
11
8
9
8
June
7.9
5
9
10
6
July
3.1
3
4
2
2
August
4.7
2
8
5
3
September
7.0
9
7
4
11
October
10.0
16
10
4
6
November
10.8
3
29
7
9
December
11.8
6
28
10
4
Average
9.3
14.3
10.1
12.5
6.5
6.9
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
7.0
7
6
8
6
7
February
8.0
8
8
8
8
8
March
8.6
9
8
9
9
8
April
9.0
10
10
10
8
10
May
7.3
7
8
7
8
June
7.0
6
8
7
7
July
6.2
6
7
6
6
August
6.3
7
6
6
6
September
6.8
7
7
7
7
October
7.6
7
7
7
8
November
7.9
8
8
8
8
December
7.2
7
7
8
7
Average
7.5
8.6
7.1
7.7
7.1
7.4
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
299°
296°
273°
328°
280°
February
272°
287°
296°
284°
286°
March
315°
009°
330°
247°
276°
April
324°
266°
248°
287°
313°
May
047°
180°
225°
021°
June
024°
252°
248°
200°
July
291°
271°
288°
258°
August
338°
280°
234°
252°
September
134°
261°
260°
249°
October
306°
251°
035°
281°
November
267°
253°
261°
248°
December
270°
165°
258°
273°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.