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
91.3
89
83
91
93
98
February
88.0
74
95
86
89
92
March
91.6
88
78
93
98
95
April
94.7
88
95
96
96
May
97.2
99
98
93
99
June
98.6
96
99
100
99
July
99.8
100
100
100
100
August
98.7
100
100
97
100
September
96.0
96
95
99
92
October
94.4
86
96
96
93
November
93.4
100
87
99
95
December
90.8
91
79
97
98
Average
93.7
83.4
92.6
94.1
96.4
96.5
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
-1.7
-2
-2
0
3
4
February
-1.9
3
1
1
-1
2
March
6.7
9
2
10
10
7
April
12.4
12
10
14
13
May
18.6
22
16
17
19
June
24.4
22
25
30
23
July
30.5
30
32
33
29
August
29.0
28
32
28
30
September
23.4
24
26
26
25
October
13.6
14
16
16
14
November
5.3
9
-1
10
8
December
1.3
4
-5
4
4
Average
12.5
3.3
13.8
14.0
15.7
14.7
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
-12.7
-14
-12
-13
-8
-6
February
-12.5
-7
-12
-12
-13
-9
March
-6.4
-5
-9
-3
-4
-4
April
-2.4
-2
-4
-2
-2
May
4.4
7
3
3
5
June
8.3
9
8
9
8
July
11.0
11
12
13
10
August
10.3
12
12
10
10
September
6.1
7
8
5
5
October
-1.2
0
1
2
-2
November
-7.7
-5
-13
-2
-7
December
-10.0
-8
-15
-9
-9
Average
-2.5
-9.2
-1.8
-1.2
0.2
-1.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
7.3
7
12
10
7
4
February
14.0
28
7
16
10
10
March
9.5
11
23
8
1
8
April
9.3
13
8
7
8
May
6.8
4
16
6
5
June
6.9
11
4
1
12
July
1.2
2
1
1
2
August
1.7
5
0
2
1
September
5.3
6
5
1
2
October
7.9
15
10
9
9
November
7.4
2
17
3
4
December
9.2
8
19
5
5
Average
7.8
15.3
8.8
8.7
4.1
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
3.5
3
3
4
4
5
February
4.7
4
5
5
5
5
March
5.1
4
3
6
5
7
April
6.2
6
8
6
6
May
5.3
5
6
5
6
June
5.1
4
6
5
5
July
4.6
5
5
5
5
August
4.5
5
5
5
5
September
4.5
4
4
5
5
October
4.7
3
3
5
6
November
4.2
3
5
6
5
December
3.8
2
3
7
3
Average
4.6
3.7
4.1
5.0
5.2
5.2
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
237°
129°
238°
263°
250°
February
247°
273°
271°
252°
240°
March
258°
321°
287°
268°
257°
April
298°
278°
296°
276°
May
319°
273°
295°
259°
June
291°
249°
306°
296°
July
348°
333°
353°
335°
August
261°
272°
274°
321°
September
281°
306°
308°
287°
October
285°
259°
261°
261°
November
251°
253°
257°
253°
December
141°
170°
228°
252°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.