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
67.8
72
67
71
77
60
February
74.4
74
85
85
83
94
March
80.7
90
78
95
94
87
April
87.0
86
85
75
92
95
May
91.7
97
90
92
83
June
96.2
93
98
97
97
July
98.0
97
97
98
98
August
93.9
92
96
95
94
September
91.7
86
95
95
96
October
89.6
91
99
84
92
November
86.6
96
83
96
90
December
75.7
75
47
76
87
Average
86.6
81.4
87.7
88.7
90.7
90.0
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
-7.6
-5
-8
-9
-3
-8
February
-5.7
3
-5
-7
-10
-5
March
1.6
3
-5
1
9
2
April
8.8
13
5
6
12
9
May
19.7
23
18
20
17
June
26.5
27
26
29
27
July
27.7
26
28
30
28
August
25.9
26
27
28
26
September
21.5
23
23
24
20
October
11.4
13
15
15
8
November
2.7
5
1
6
7
December
-4.5
2
-7
-6
0
Average
10.0
3.6
11.0
10.7
13.1
11.0
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
-15.6
-14
-15
-21
-10
-15
February
-13.1
-7
-16
-20
-19
-13
March
-7.0
-7
-15
-8
-4
-6
April
-2.5
1
-4
-3
-1
-2
May
7.1
10
7
6
6
June
14.0
16
14
14
15
July
15.6
14
16
17
17
August
14.3
15
15
15
15
September
10.0
11
10
11
9
October
1.7
2
2
5
0
November
-7.5
-5
-8
-4
-6
December
-12.2
-7
-15
-15
-10
Average
-1.8
-7.3
0.6
-1.6
1.4
0.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
32.5
36
36
43
24
39
February
28.0
26
42
53
24
30
March
22.7
32
43
25
11
23
April
20.3
23
30
35
18
17
May
6.6
6
8
4
8
June
4.3
7
0
3
7
July
2.5
3
1
1
1
August
3.2
4
2
4
3
September
5.8
5
3
6
4
October
14.5
14
5
13
15
November
23.0
18
39
14
13
December
28.3
22
50
35
26
Average
16.0
28.7
17.8
18.6
11.6
13.9
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
10.4
10
10
13
10
12
February
10.0
11
12
15
10
11
March
10.4
12
12
13
12
12
April
12.0
13
12
14
12
11
May
10.4
11
11
11
9
June
9.7
8
10
9
11
July
8.4
8
9
8
9
August
8.7
9
9
10
8
September
10.0
8
10
10
11
October
11.5
11
11
11
12
November
10.9
12
12
9
12
December
11.0
10
12
11
11
Average
10.3
11.5
10.1
11.5
10.2
10.6
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
283°
286°
289°
296°
254°
February
288°
274°
297°
273°
273°
March
333°
347°
308°
217°
287°
April
339°
349°
358°
340°
313°
May
151°
261°
238°
062°
June
093°
265°
279°
186°
July
294°
281°
200°
241°
August
314°
233°
216°
200°
September
085°
280°
234°
281°
October
315°
294°
326°
285°
November
283°
278°
278°
252°
December
302°
318°
296°
292°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.