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
76.6
63
68
74
83
86
February
85.3
90
90
84
83
79
March
86.4
83
80
84
95
87
April
91.9
95
91
96
90
May
90.4
95
86
94
92
June
93.0
81
94
98
99
July
95.6
90
96
94
98
August
94.7
92
94
95
98
September
95.2
96
93
95
92
October
91.0
91
98
92
91
November
91.4
90
90
95
95
December
84.4
80
85
88
80
Average
88.7
77.1
87.4
89.6
92.6
91.1
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
2.0
1
5
-1
2
4
February
5.1
8
9
3
-1
3
March
9.0
12
8
11
13
11
April
15.0
17
14
16
13
May
21.2
21
23
21
20
June
26.0
25
28
27
27
July
27.9
28
28
27
30
August
26.4
26
27
28
27
September
23.9
23
23
25
23
October
18.0
18
17
21
16
November
9.5
11
12
9
13
December
5.3
8
5
8
4
Average
14.7
7.0
16.5
16.1
16.1
15.8
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
-5.6
-4
0
-9
-3
-2
February
-4.5
0
-2
-6
-8
-3
March
-1.9
2
0
1
2
2
April
4.4
5
4
6
3
May
10.4
8
13
10
10
June
15.6
14
17
18
15
July
18.2
17
19
18
19
August
16.5
15
17
18
16
September
14.0
14
14
14
12
October
8.4
9
6
12
8
November
1.3
1
3
0
4
December
-2.8
3
0
0
-1
Average
5.7
-1.3
6.9
6.8
7.3
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
23.7
30
27
28
12
21
February
17.7
10
17
25
19
15
March
16.8
16
27
21
4
13
April
11.4
13
15
8
12
May
9.1
9
12
7
12
June
4.7
5
4
6
2
July
3.5
5
5
6
2
August
4.6
7
3
4
5
September
4.8
4
7
6
3
October
7.5
6
7
7
8
November
11.6
10
16
8
13
December
12.4
16
4
8
13
Average
11.2
19.5
11.7
12.1
7.6
9.4
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
9.7
10
9
10
9
10
February
10.4
9
11
11
10
10
March
10.8
10
11
11
11
10
April
10.1
9
10
9
10
May
8.9
8
9
8
9
June
8.2
8
8
8
8
July
6.7
6
8
6
7
August
5.9
6
6
5
6
September
6.6
5
7
8
7
October
8.0
7
9
7
8
November
9.5
8
10
9
11
December
9.0
8
9
9
9
Average
8.7
9.8
7.7
8.8
8.2
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
247°
250°
273°
270°
243°
February
250°
248°
239°
276°
275°
March
267°
281°
257°
263°
268°
April
258°
256°
267°
291°
May
012°
176°
349°
270°
June
354°
288°
237°
309°
July
276°
264°
299°
287°
August
298°
254°
277°
291°
September
338°
276°
246°
217°
October
268°
237°
219°
241°
November
250°
238°
244°
247°
December
239°
237°
228°
246°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.