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
61.9
62
68
64
79
67
February
84.5
75
88
78
84
94
March
86.8
90
81
93
96
89
April
87.3
84
72
88
92
May
93.1
94
89
89
92
June
96.3
95
98
98
98
July
97.4
99
93
98
97
August
91.8
93
84
87
94
September
91.0
87
96
99
99
October
87.8
79
91
93
88
November
76.7
83
78
77
78
December
80.3
92
50
84
86
Average
86.3
76.6
87.6
84.7
90.0
90.6
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
-8.7
-8
-8
-10
-5
-8
February
-8.6
0
-4
-10
-11
-4
March
-1.3
-1
-6
-2
7
3
April
7.4
4
3
11
7
May
18.7
23
16
18
17
June
24.6
27
24
26
26
July
25.1
24
25
27
25
August
24.1
25
23
25
25
September
19.7
22
22
23
19
October
9.7
10
12
14
6
November
0.5
2
0
3
4
December
-5.2
1
-10
-8
-1
Average
7.7
-3.1
10.0
8.4
10.9
9.8
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
-16.8
-15
-17
-22
-12
-17
February
-19.9
-9
-18
-23
-22
-15
March
-11.7
-11
-17
-10
-6
-8
April
-4.4
-4
-5
-4
-4
May
5.1
8
5
3
4
June
12.0
14
12
13
12
July
13.7
11
15
15
15
August
11.2
12
11
12
11
September
7.5
10
8
9
6
October
0.0
1
1
3
-2
November
-9.5
-6
-9
-7
-8
December
-14.1
-8
-17
-18
-11
Average
-3.1
-12.5
-1.0
-3.6
-1.0
-2.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.9
15
14
17
13
11
February
10.8
9
5
13
8
10
March
7.8
10
11
7
4
6
April
7.6
15
15
5
11
May
2.6
1
8
1
3
June
1.9
2
1
3
1
July
0.8
1
2
1
1
August
1.7
3
0
2
2
September
3.1
3
2
0
1
October
6.9
11
2
3
6
November
14.6
9
27
9
9
December
11.0
6
28
9
8
Average
6.6
11.2
6.0
8.3
4.2
5.1
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
9.4
11
6
13
10
10
February
10.9
9
11
15
10
11
March
11.6
12
11
13
12
12
April
11.9
14
13
12
12
May
11.7
11
14
12
11
June
10.8
8
12
11
12
July
8.8
8
10
9
9
August
7.9
8
7
9
8
September
10.4
9
11
10
12
October
11.9
10
12
12
13
November
10.9
12
12
11
11
December
10.1
12
8
10
10
Average
10.5
10.6
9.9
11.6
10.7
10.9
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
280°
269°
293°
276°
263°
February
282°
285°
309°
279°
270°
March
327°
332°
292°
249°
270°
April
351°
008°
333°
299°
May
058°
265°
310°
205°
June
027°
266°
284°
236°
July
283°
302°
199°
242°
August
306°
263°
282°
253°
September
212°
281°
263°
278°
October
328°
310°
302°
284°
November
278°
282°
268°
252°
December
278°
284°
262°
284°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.