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
74.7
54
57
90
82
64
February
86.6
87
89
87
85
91
March
88.1
87
80
92
92
86
April
88.9
89
90
84
90
96
May
95.4
96
97
99
95
June
97.6
96
100
99
99
July
96.7
96
98
93
99
August
95.0
97
96
97
97
September
94.6
94
98
96
97
October
92.2
89
100
94
93
November
91.3
97
87
98
94
December
75.2
64
57
84
87
Average
89.4
80.3
88.1
92.5
92.9
92.3
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
-5.2
-5
-5
-7
-2
-4
February
-3.1
4
-3
-4
-8
-3
March
4.3
7
0
4
10
6
April
11.5
14
10
8
14
13
May
21.6
25
21
22
20
June
28.2
29
29
31
29
July
28.3
28
29
30
29
August
26.4
28
27
28
27
September
23.4
25
24
25
22
October
13.9
15
17
18
11
November
5.3
8
5
7
9
December
-1.7
4
-2
-1
1
Average
11.9
5.0
13.8
13.0
14.6
13.3
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
-13.1
-11
-13
-18
-9
-13
February
-14.9
-6
-14
-16
-15
-13
March
-5.3
-5
-9
-4
-1
-2
April
1.0
3
1
1
2
1
May
9.4
11
10
9
9
June
15.9
16
17
17
16
July
16.6
12
18
18
18
August
16.0
17
17
16
17
September
12.3
13
12
12
10
October
3.6
4
4
6
2
November
-4.1
-4
-3
-3
-2
December
-9.4
-4
-8
-10
-8
Average
1.7
-5.2
2.6
2.6
3.6
2.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.3
13
18
6
8
16
February
5.2
6
7
9
8
8
March
6.5
15
15
2
11
6
April
8.0
12
15
13
11
4
May
5.4
3
3
6
8
June
2.9
4
3
4
3
July
2.5
2
3
4
3
August
2.3
3
2
2
1
September
2.6
2
3
5
3
October
5.3
5
4
6
10
November
4.5
4
13
3
3
December
9.5
17
22
16
8
Average
5.7
11.5
7.3
5.9
6.6
5.6
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
8.7
9
7
9
9
9
February
9.2
11
9
12
9
8
March
10.1
12
10
10
10
9
April
11.3
14
11
15
11
10
May
9.2
9
10
8
10
June
8.2
7
9
7
9
July
6.0
6
8
5
6
August
6.3
7
7
7
6
September
7.3
7
7
8
7
October
9.2
10
9
8
10
November
9.9
11
11
10
9
December
9.1
9
11
9
9
Average
9.0
11.7
8.5
9.7
8.2
8.4
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
285°
322°
303°
324°
304°
February
274°
350°
304°
286°
294°
March
343°
007°
335°
105°
325°
April
345°
330°
298°
336°
319°
May
112°
235°
211°
010°
June
097°
253°
282°
113°
July
301°
279°
137°
236°
August
036°
120°
177°
149°
September
123°
173°
243°
277°
October
291°
273°
133°
286°
November
264°
283°
282°
266°
December
242°
156°
288°
299°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.