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
87.3
84
64
96
92
84
February
89.7
79
93
95
92
93
March
88.3
93
87
84
93
96
April
90.2
87
83
92
96
May
95.9
92
97
92
99
June
97.5
100
98
96
96
July
95.0
89
91
91
99
August
92.7
90
96
84
100
September
93.3
94
94
99
100
October
93.8
92
98
94
99
November
83.5
93
67
91
87
December
88.5
92
72
90
91
Average
91.3
85.5
89.9
90.0
92.1
95.5
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
-8
-5
-5
-4
-9
February
-8.4
-2
-5
-11
-11
-3
March
1.0
0
-5
1
7
2
April
9.8
7
7
11
14
May
20.1
23
19
18
19
June
24.3
27
24
26
22
July
27.2
26
27
29
26
August
26.6
28
29
24
29
September
20.7
24
22
22
21
October
10.2
9
12
13
8
November
0.3
2
-3
5
3
December
-4.8
3
-12
-6
-1
Average
9.3
-3.0
11.4
9.7
11.9
11.4
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
-14.3
-16
-10
-14
-10
-16
February
-16.7
-10
-13
-19
-19
-11
March
-9.7
-9
-13
-7
-5
-8
April
-1.5
-2
-2
-2
0
May
7.3
9
6
3
8
June
12.4
15
10
12
11
July
14.3
13
14
14
13
August
13.0
14
14
12
12
September
8.8
10
9
9
8
October
1.1
2
3
1
-1
November
-6.0
-5
-8
-4
-4
December
-10.5
-5
-17
-12
-8
Average
-1.3
-12.4
1.6
-1.5
0.7
0.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
26.8
40
36
18
26
25
February
25.0
29
18
29
35
14
March
18.0
17
32
26
11
5
April
11.6
17
24
8
16
May
5.4
9
9
9
1
June
7.0
3
9
8
4
July
3.1
6
8
5
3
August
4.8
5
5
10
1
September
7.6
3
9
0
4
October
9.0
15
6
9
5
November
17.9
3
51
11
2
December
22.6
5
68
22
13
Average
13.6
28.0
12.0
19.1
11.3
6.5
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
10.5
11
10
11
10
11
February
10.6
10
12
12
13
11
March
11.1
10
11
14
11
12
April
11.2
11
15
10
13
May
10.5
10
12
11
12
June
10.3
9
11
12
12
July
9.6
11
9
9
10
August
9.0
11
9
10
10
September
10.5
10
11
13
12
October
11.1
12
12
10
13
November
11.3
11
14
11
12
December
10.8
12
11
12
9
Average
10.5
10.2
10.6
11.8
10.8
11.3
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
258°
270°
238°
215°
278°
February
245°
276°
277°
287°
268°
March
277°
208°
274°
229°
278°
April
046°
151°
283°
260°
May
128°
283°
219°
262°
June
225°
274°
276°
290°
July
291°
297°
063°
270°
August
262°
266°
333°
292°
September
235°
263°
274°
285°
October
292°
277°
245°
289°
November
263°
274°
243°
241°
December
251°
280°
256°
260°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.