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
63.6
53
64
49
76
75
February
75.6
60
85
81
81
86
March
90.3
89
84
88
95
93
April
95.6
96
96
100
96
May
97.0
97
94
100
93
June
98.6
99
95
100
98
July
99.8
100
100
99
100
August
92.7
87
100
83
100
September
90.3
97
89
99
77
October
94.5
94
96
95
95
November
71.8
55
69
80
82
December
58.1
51
26
76
55
Average
85.0
67.5
85.2
84.7
91.1
88.5
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
1.6
1
2
1
3
4
February
3.1
6
4
4
2
6
March
9.4
11
8
11
11
9
April
13.9
13
11
17
15
May
21.0
25
16
21
20
June
25.1
26
23
30
23
July
30.9
32
31
34
29
August
30.4
30
33
30
30
September
23.5
23
27
23
25
October
14.8
16
19
15
15
November
5.7
6
2
8
6
December
1.6
4
-2
1
3
Average
14.0
5.6
15.8
15.2
16.2
15.4
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
-4.8
-4
-2
-4
-1
-1
February
-4.1
0
-4
-4
-4
-2
March
-1.9
1
-1
2
0
0
April
3.1
3
1
4
3
May
8.8
12
6
7
8
June
12.2
13
12
15
11
July
15.8
16
16
18
14
August
15.7
16
17
15
15
September
10.8
11
12
11
12
October
4.4
6
7
5
4
November
-1.5
0
-5
2
0
December
-3.1
-1
-6
-4
-2
Average
4.3
-2.7
5.8
4.9
5.6
5.1
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
18.6
29
13
13
21
26
February
19.8
27
11
12
15
8
March
12.5
13
13
15
4
13
April
10.8
10
10
6
5
May
7.5
4
13
4
13
June
5.7
3
13
2
10
July
1.0
0
2
1
1
August
1.8
5
0
1
1
September
5.2
5
4
5
1
October
7.1
5
6
9
8
November
14.4
16
17
17
12
December
17.3
22
17
15
15
Average
11.0
22.6
8.4
9.7
7.5
9.0
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
6.8
7
6
6
7
10
February
8.2
8
9
7
10
9
March
8.5
8
8
9
9
10
April
9.6
9
11
10
9
May
7.9
6
9
9
9
June
8.5
7
9
8
9
July
7.5
8
7
7
9
August
7.2
7
7
8
8
September
7.3
7
6
8
7
October
7.7
6
7
8
9
November
7.1
6
7
8
9
December
6.4
6
5
9
7
Average
7.7
7.4
7.0
7.7
8.5
8.5
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
112°
095°
184°
164°
201°
February
210°
196°
181°
220°
222°
March
200°
148°
215°
213°
220°
April
208°
207°
206°
227°
May
175°
213°
219°
195°
June
203°
210°
203°
212°
July
214°
210°
195°
207°
August
197°
192°
214°
208°
September
186°
146°
212°
190°
October
144°
202°
199°
215°
November
171°
116°
196°
194°
December
091°
141°
208°
172°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.