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
81.8
63
72
86
93
89
February
90.4
84
86
89
92
94
March
87.2
90
92
79
94
95
April
93.8
92
94
98
97
May
94.8
81
98
98
96
June
96.5
91
98
99
95
July
94.0
91
94
88
97
August
93.7
89
98
95
99
September
93.3
85
99
97
99
October
95.5
94
93
96
98
November
88.6
90
84
93
87
December
89.3
100
76
85
90
Average
90.8
79.1
88.4
91.5
94.2
95.0
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
-5.1
-9
-4
-4
-2
-10
February
-6.9
-1
-3
-2
-10
-1
March
1.4
1
0
3
8
-1
April
9.7
12
9
13
8
May
19.3
24
17
17
17
June
22.1
24
21
25
21
July
23.8
24
24
26
23
August
23.3
23
26
25
23
September
18.2
20
23
20
19
October
10.7
11
16
11
7
November
1.1
5
-1
4
1
December
-4.4
3
-10
-11
0
Average
8.2
-3.0
11.7
10.9
10.5
8.9
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
-15.9
-19
-12
-14
-11
-18
February
-15.1
-11
-12
-12
-20
-11
March
-10.5
-9
-12
-7
-5
-11
April
-3.7
-1
-3
-4
-3
May
5.7
8
4
4
5
June
10.2
11
10
12
10
July
11.9
12
13
13
12
August
10.5
11
12
11
10
September
5.8
6
7
7
7
October
-1.1
-1
2
-1
-2
November
-9.9
-5
-10
-8
-9
December
-13.1
-8
-21
-19
-9
Average
-3.1
-14.8
-1.8
-1.0
-2.3
-2.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
19.1
29
12
35
15
10
February
17.1
17
26
28
16
11
March
16.6
26
24
29
9
11
April
9.9
8
20
6
9
May
7.1
4
9
10
11
June
10.8
19
15
3
12
July
6.9
10
12
2
11
August
6.1
10
7
6
3
September
5.9
5
3
4
2
October
8.1
14
7
5
14
November
16.6
0
35
8
12
December
15.3
1
32
26
9
Average
12.3
23.9
11.4
18.0
8.3
9.4
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
6.5
5
6
8
8
6
February
7.3
7
7
9
8
7
March
7.3
8
6
10
8
9
April
8.6
8
10
8
10
May
8.6
9
9
9
9
June
8.3
8
9
8
8
July
6.9
7
7
7
8
August
7.2
6
7
8
8
September
7.9
7
7
9
9
October
8.5
8
8
8
9
November
7.0
6
10
7
7
December
6.8
5
8
7
6
Average
7.5
6.4
7.1
8.3
7.9
8.1
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
001°
267°
305°
269°
274°
February
325°
306°
302°
294°
286°
March
145°
088°
314°
245°
314°
April
174°
338°
304°
294°
May
146°
310°
287°
354°
June
331°
325°
286°
301°
July
304°
333°
290°
278°
August
288°
256°
294°
259°
September
252°
281°
267°
297°
October
281°
274°
248°
288°
November
276°
328°
244°
278°
December
190°
299°
292°
276°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.