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
71.4
62
70
91
67
58
February
85.2
96
86
92
82
96
March
86.7
93
87
85
88
78
April
89.4
90
87
100
93
90
May
92.6
95
99
92
93
June
95.4
97
98
97
97
July
93.4
98
83
92
97
August
92.9
96
90
95
99
September
93.6
93
97
95
96
October
90.8
89
99
96
91
November
86.4
98
76
99
86
December
76.7
69
83
80
86
Average
88.1
85.7
89.5
91.0
90.3
89.7
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
-4
-4
-7
-3
-4
February
-3.1
6
-2
-5
-9
-3
March
4.2
9
2
5
7
5
April
11.9
14
12
9
14
12
May
20.4
23
21
20
19
June
26.8
27
27
30
28
July
27.1
27
27
27
28
August
23.8
28
25
27
15
September
22.8
25
22
24
20
October
13.5
15
15
17
10
November
4.9
8
5
7
9
December
-1.6
4
-2
1
1
Average
11.5
5.9
13.8
12.7
13.5
11.5
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
-12.0
-10
-10
-18
-10
-11
February
-13.8
-6
-11
-15
-16
-13
March
-4.3
-3
-6
-4
-1
-1
April
1.6
3
2
2
3
0
May
9.2
10
10
9
9
June
15.6
15
16
17
15
July
16.1
15
17
17
17
August
13.8
16
15
15
8
September
11.8
14
11
11
10
October
3.8
5
3
7
1
November
-4.5
-3
-3
-2
-1
December
-9.9
-4
-8
-8
-8
Average
1.9
-4.2
3.7
2.5
3.4
2.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
10.5
11
16
2
6
13
February
10.3
2
13
11
12
4
March
7.9
8
14
6
8
2
April
9.9
12
10
10
5
3
May
6.7
6
6
11
1
June
3.3
3
6
0
0
July
2.7
1
2
4
0
August
3.0
2
5
1
0
September
3.3
5
3
1
1
October
6.7
8
3
5
2
November
6.1
4
15
0
0
December
8.1
6
16
0
0
Average
6.7
8.3
6.9
6.0
4.4
1.8
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
8.9
8
7
11
8
9
February
9.8
11
9
12
9
10
March
10.3
11
10
11
11
10
April
11.5
14
13
14
11
11
May
9.7
10
11
10
10
June
9.0
7
11
8
10
July
6.5
6
8
6
6
August
6.6
7
7
7
7
September
7.8
7
8
7
8
October
9.5
9
10
8
10
November
11.0
10
12
12
11
December
9.3
9
11
10
9
Average
9.3
11.1
8.6
9.9
8.8
9.2
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
266°
279°
237°
266°
247°
February
238°
241°
276°
271°
259°
March
305°
283°
314°
176°
224°
April
265°
253°
100°
267°
292°
May
145°
172°
172°
033°
June
133°
219°
236°
166°
July
255°
230°
223°
217°
August
227°
198°
193°
209°
September
177°
205°
220°
229°
October
280°
237°
171°
263°
November
231°
234°
242°
225°
December
218°
164°
219°
245°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.