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
70.3
60
68
97
67
60
February
88.9
89
83
94
82
99
March
85.2
92
84
93
79
80
April
90.9
94
92
83
95
May
88.8
92
96
80
90
June
89.2
94
97
66
95
July
92.3
94
94
90
87
August
95.2
93
95
96
96
September
91.7
95
100
97
95
October
88.9
84
99
86
88
November
92.7
100
92
93
89
December
81.5
73
66
99
85
Average
87.5
81.2
88.3
94.0
84.4
88.4
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
-3.5
-5
-4
0
-1
-2
February
0.6
8
-1
2
-7
1
March
8.3
10
3
9
11
9
April
14.9
16
14
15
15
May
21.0
25
22
20
19
June
28.5
29
29
28
30
July
28.5
28
29
28
30
August
27.4
28
28
28
28
September
24.8
26
27
26
24
October
15.1
16
18
18
13
November
8.2
11
6
9
10
December
2.0
5
-2
4
3
Average
13.7
4.2
15.0
15.8
15.0
15.2
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
-11.2
-11
-11
-14
-7
-10
February
-10.2
-4
-10
-13
-15
-8
March
-3.6
-3
-6
-3
0
-1
April
1.6
3
1
2
1
May
9.1
12
10
5
10
June
14.2
17
17
7
15
July
16.0
16
18
17
11
August
16.5
17
16
17
17
September
12.4
14
12
13
11
October
3.9
6
4
7
2
November
-3.5
-2
-4
-2
-1
December
-7.1
-4
-10
-7
-8
Average
2.7
-6.0
4.3
3.3
3.3
3.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
10.1
18
13
3
7
9
February
6.0
5
7
6
10
2
March
7.7
7
12
5
8
6
April
5.1
9
5
3
4
May
4.0
2
1
4
6
June
3.0
3
2
3
3
July
3.2
5
3
4
2
August
1.7
2
3
1
1
September
2.2
4
1
3
3
October
3.6
4
2
5
3
November
6.1
5
15
3
5
December
7.4
8
19
1
6
Average
5.4
9.9
5.9
4.4
4.1
4.0
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
11.5
11
10
13
12
12
February
12.0
12
12
14
10
12
March
13.7
15
13
15
13
13
April
15.0
16
19
13
12
May
11.8
12
14
10
12
June
9.3
8
11
5
12
July
7.8
7
8
8
7
August
8.4
8
8
9
9
September
9.5
10
10
10
11
October
12.1
12
12
12
12
November
12.9
13
15
13
12
December
12.0
11
14
13
12
Average
11.3
12.8
10.9
12.5
10.4
11.2
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
282°
303°
267°
309°
284°
February
251°
191°
306°
265°
320°
March
349°
349°
334°
134°
226°
April
292°
263°
307°
305°
May
143°
201°
142°
001°
June
140°
223°
234°
166°
July
183°
196°
151°
160°
August
159°
167°
151°
173°
September
176°
171°
164°
221°
October
296°
249°
185°
276°
November
238°
274°
254°
227°
December
261°
205°
276°
283°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.