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
76.9
67
82
92
74
66
February
88.3
94
89
96
82
93
March
88.6
96
92
89
91
80
April
81.5
90
95
93
18
93
May
91.2
96
93
92
92
June
94.9
89
96
97
96
July
94.5
91
94
92
94
August
94.2
93
96
90
99
September
89.5
94
96
98
85
October
91.3
92
96
87
93
November
91.0
97
92
95
90
December
85.2
78
80
87
87
Average
89.0
88.5
90.9
93.3
83.3
89.3
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
-1.9
0
2
-2
0
1
February
3.6
11
6
3
-6
3
March
10.1
14
9
11
12
12
April
15.1
18
19
15
5
16
May
23.0
25
24
21
21
June
28.8
29
30
29
29
July
29.5
29
30
29
30
August
27.8
28
28
28
29
September
25.5
27
25
27
24
October
17.7
19
19
20
16
November
9.6
12
11
12
14
December
5.0
7
4
8
4
Average
15.6
11.1
17.6
16.7
15.4
16.4
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
-8.2
-6
-5
-13
-6
-6
February
-7.1
-2
-5
-10
-13
-6
March
-1.9
2
-1
-1
2
2
April
3.7
6
4
3
0
4
May
11.6
11
13
11
11
June
17.2
15
17
18
18
July
18.2
15
19
19
19
August
16.7
18
18
16
16
September
12.8
14
13
14
12
October
6.3
8
4
10
4
November
-1.1
0
-1
0
2
December
-5.9
0
-4
-3
-5
Average
4.8
0.2
6.1
5.0
5.7
5.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
7.4
4
9
6
7
9
February
6.3
1
10
4
10
2
March
5.3
4
7
9
4
7
April
4.2
8
3
5
0
2
May
3.4
1
3
5
4
June
2.8
2
1
4
6
July
2.0
1
2
5
3
August
1.2
1
1
1
0
September
3.1
1
2
1
6
October
3.7
3
1
7
3
November
4.4
2
10
3
4
December
4.9
9
8
1
5
Average
4.0
4.4
3.7
3.9
3.8
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
10.3
8
10
11
9
10
February
10.8
11
11
12
10
10
March
11.7
13
11
12
12
11
April
11.1
13
13
13
2
12
May
9.9
10
11
10
10
June
8.5
8
9
7
9
July
6.6
6
8
6
6
August
6.4
7
7
6
7
September
7.2
7
8
8
8
October
9.8
11
10
10
10
November
10.6
10
12
11
11
December
9.9
9
11
11
9
Average
9.5
11.5
9.2
10.2
8.2
9.4
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
265°
284°
281°
329°
276°
February
256°
251°
282°
312°
311°
March
294°
291°
307°
155°
248°
April
267°
251°
245°
205°
273°
May
118°
156°
165°
350°
June
049°
221°
217°
184°
July
295°
246°
282°
175°
August
250°
103°
179°
201°
September
184°
287°
235°
244°
October
288°
252°
345°
277°
November
247°
245°
252°
226°
December
245°
206°
235°
277°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.