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
81.3
73
73
80
81
80
February
88.1
73
85
93
89
98
March
86.0
77
76
89
96
94
April
88.8
94
87
75
91
95
May
94.5
91
93
92
96
June
96.1
91
96
96
98
July
97.7
97
96
96
99
August
93.8
91
93
88
98
September
92.2
83
96
100
99
October
89.8
75
95
87
94
November
83.6
86
80
94
86
December
84.2
93
52
86
92
Average
89.4
79.8
85.8
88.1
91.8
94.6
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
-5.2
-6
-4
-5
0
-5
February
-5.5
2
-3
-4
-8
1
March
2.8
2
-4
4
11
6
April
11.1
14
8
6
14
11
May
21.3
24
20
20
20
June
27.1
28
26
30
27
July
29.5
28
29
32
28
August
28.5
28
30
29
29
September
22.7
24
26
27
22
October
12.5
12
15
17
9
November
3.9
6
1
8
8
December
-2.4
3
-8
-4
2
Average
11.2
2.9
12.5
12.2
14.7
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
-14.5
-14
-13
-17
-9
-13
February
-15.7
-7
-13
-17
-18
-10
March
-8.6
-9
-14
-7
-3
-5
April
-1.0
1
-2
-3
0
-2
May
7.3
9
7
6
6
June
13.3
14
12
15
13
July
15.9
14
17
17
16
August
14.0
15
15
15
14
September
9.8
11
10
11
8
October
1.9
2
3
5
0
November
-6.3
-4
-8
-3
-5
December
-11.5
-6
-16
-14
-8
Average
-1.9
-8.9
1.0
0.3
2.1
1.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
12.7
24
8
21
12
5
February
9.5
8
14
8
8
4
March
10.7
22
19
9
0
5
April
10.5
12
16
23
9
7
May
4.9
11
10
2
4
June
3.0
1
3
3
1
July
1.7
3
2
0
3
August
3.0
6
2
4
1
September
5.3
6
1
2
3
October
7.0
16
3
8
4
November
13.0
11
21
10
5
December
11.7
8
35
11
5
Average
8.1
16.2
9.6
10.1
5.0
3.6
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
11.0
11
9
13
10
10
February
11.0
10
12
13
11
10
March
11.4
11
11
13
11
11
April
12.2
13
13
15
12
12
May
10.9
9
12
11
11
June
9.8
7
10
10
11
July
8.9
9
9
9
9
August
8.4
8
8
9
8
September
10.1
8
10
10
12
October
11.8
11
11
11
13
November
10.8
10
14
11
11
December
10.4
10
11
11
10
Average
10.6
11.1
9.7
11.7
10.5
10.7
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
266°
258°
273°
261°
258°
February
282°
268°
282°
272°
255°
March
301°
305°
280°
250°
255°
April
284°
336°
331°
297°
286°
May
019°
262°
252°
138°
June
346°
255°
281°
247°
July
270°
286°
154°
242°
August
286°
265°
264°
229°
September
232°
282°
257°
262°
October
304°
289°
286°
269°
November
262°
269°
261°
243°
December
259°
302°
258°
256°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.