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
79.3
71
74
84
88
February
88.6
88
89
89
87
100
March
91.3
90
87
97
93
100
April
92.5
96
93
91
93
100
May
96.7
98
96
100
95
June
98.3
99
100
99
97
July
98.2
99
99
94
100
August
95.6
97
97
96
96
September
95.4
95
98
96
99
October
93.9
92
99
92
94
November
93.1
99
90
94
99
December
78.2
75
67
87
88
Average
92.1
88.3
92.1
93.7
93.5
96.1
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
-5.7
-2
-5
-6
-1
February
-3.1
6
-2
-4
-8
3
March
4.0
8
-1
4
10
2
April
11.7
16
10
9
14
10
May
21.7
25
21
22
18
June
28.3
30
28
33
30
July
29.0
29
30
31
30
August
27.0
30
28
28
28
September
24.0
26
26
24
22
October
14.4
16
18
17
11
November
5.9
10
5
7
10
December
-1.9
6
-2
-1
2
Average
12.8
7.5
14.5
13.4
13.9
16.9
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
-13.0
-8
-13
-20
-9
February
-13.0
-5
-14
-17
-17
3
March
-5.3
-4
-11
-5
-1
0
April
1.5
4
0
0
2
4
May
9.7
11
10
9
9
June
15.1
17
5
18
18
July
16.6
15
10
19
18
August
16.1
17
16
17
17
September
12.4
14
11
13
10
October
4.0
5
4
7
1
November
-4.3
-3
-4
-3
-2
December
-9.1
-3
-10
-11
-9
Average
2.3
-4.9
3.1
0.4
3.1
6.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.8
13
22
7
7
February
7.3
4
9
10
6
0
March
8.9
12
15
2
8
0
April
12.5
13
11
16
12
0
May
6.2
5
5
5
8
June
3.1
3
2
2
5
July
2.6
2
3
4
2
August
3.1
3
3
3
1
September
3.5
2
2
10
5
October
6.0
7
3
7
7
November
6.8
6
12
3
1
December
10.8
11
21
9
7
Average
6.8
10.3
7.3
6.2
6.1
4.1
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
8.0
8
7
9
8
February
8.7
8
7
12
7
9
March
9.9
10
9
11
10
10
April
11.4
12
10
14
11
8
May
8.9
9
10
9
8
June
7.8
7
9
7
8
July
6.1
6
7
5
4
August
6.4
7
7
7
6
September
6.9
6
7
7
7
October
8.7
9
9
9
9
November
9.2
9
10
9
9
December
8.3
7
10
8
8
Average
8.3
10.0
7.7
9.5
8.1
7.2
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
311°
003°
312°
327°
February
280°
028°
312°
280°
119°
March
342°
031°
336°
150°
315°
April
340°
028°
323°
333°
326°
May
161°
232°
245°
045°
June
155°
246°
245°
141°
July
351°
296°
166°
202°
August
293°
128°
150°
159°
September
125°
213°
298°
288°
October
311°
316°
176°
293°
November
279°
335°
289°
261°
December
290°
041°
299°
319°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.