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
84.9
80
72
93
88
82
February
87.8
90
84
85
94
95
March
89.6
87
81
90
94
92
April
85.2
84
81
81
84
92
May
87.3
87
82
86
91
June
88.6
77
91
85
93
July
92.3
92
87
88
96
August
86.9
89
86
81
87
September
86.6
87
87
89
87
October
91.2
90
96
80
94
November
92.4
99
83
95
93
December
85.1
79
77
83
93
Average
88.0
85.2
84.6
86.8
86.8
91.1
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
-3
-3
-7
-3
-3
February
-4.8
2
-2
-6
-7
-2
March
2.6
5
1
1
6
4
April
6.8
9
6
4
9
6
May
13.6
12
13
17
13
June
19.9
18
23
24
20
July
24.9
24
24
26
25
August
23.4
23
23
26
24
September
19.0
20
20
20
19
October
11.9
13
14
14
9
November
3.6
6
4
6
7
December
-2.7
3
-2
-2
-1
Average
8.8
3.1
9.4
9.6
11.3
10.0
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
-12.4
-9
-9
-18
-10
-9
February
-13.8
-5
-11
-17
-16
-12
March
-5.1
-3
-7
-7
-2
-2
April
0.2
2
-1
-1
2
0
May
5.2
4
5
6
6
June
10.6
10
9
14
12
July
15.6
14
13
17
17
August
15.3
15
14
17
17
September
12.0
14
11
14
10
October
5.4
7
4
8
2
November
-3.4
-2
-1
-1
-1
December
-8.7
-2
-8
-10
-8
Average
1.3
-4.2
2.3
0.6
3.2
2.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
12.4
15
22
6
12
13
February
12.7
5
18
13
8
8
March
8.8
15
21
9
5
5
April
12.0
16
17
14
11
5
May
6.9
8
11
3
3
June
4.4
7
4
5
3
July
3.5
3
6
3
4
August
4.8
1
5
3
3
September
5.5
9
3
4
3
October
10.2
14
5
10
8
November
10.5
7
23
6
6
December
14.7
15
25
12
9
Average
9.0
12.9
11.6
9.1
6.4
5.3
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
7.3
8
10
10
7
8
February
8.9
10
10
10
8
9
March
9.0
11
12
11
10
9
April
10.6
14
12
13
8
11
May
8.6
9
9
8
8
June
8.1
7
10
7
9
July
7.2
7
9
8
6
August
8.3
9
9
10
8
September
9.0
10
9
8
9
October
9.5
10
10
9
10
November
9.5
11
10
11
8
December
7.8
9
9
10
7
Average
8.8
11.0
9.5
9.8
8.4
8.5
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
260°
290°
256°
255°
274°
February
301°
284°
291°
258°
256°
March
346°
035°
330°
011°
020°
April
033°
025°
026°
025°
348°
May
042°
026°
041°
028°
June
052°
280°
017°
022°
July
330°
285°
045°
342°
August
051°
016°
284°
348°
September
058°
009°
327°
258°
October
359°
288°
046°
270°
November
250°
286°
280°
248°
December
294°
024°
256°
285°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.