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
75.9
55
83
88
78
63
February
87.6
95
91
89
82
92
March
85.3
91
81
90
84
79
April
93.4
98
98
94
91
May
91.9
88
88
92
90
June
98.1
98
99
95
99
July
97.1
97
96
98
95
August
94.8
91
96
98
97
September
92.5
94
90
96
86
October
91.9
93
97
93
88
November
92.1
94
94
99
90
December
85.8
74
69
96
94
Average
89.7
79.8
90.4
91.9
92.3
88.9
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
4.7
2
7
6
5
5
February
8.2
16
10
8
0
8
March
14.1
17
12
14
16
15
April
19.0
21
19
19
18
May
24.1
26
24
22
22
June
30.5
31
31
31
31
July
31.8
32
33
31
31
August
30.5
32
32
31
30
September
28.1
30
29
29
25
October
19.8
21
22
21
18
November
12.5
14
12
15
16
December
8.8
10
7
14
9
Average
18.4
11.6
20.5
20.0
19.5
18.9
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
-5.3
-7
-3
-7
-3
-3
February
-4.4
2
-3
-6
-9
-3
March
2.9
4
1
2
5
5
April
6.8
7
7
7
6
May
13.7
14
14
13
12
June
19.1
19
19
20
20
July
20.9
21
21
21
22
August
19.8
21
20
21
19
September
16.5
16
15
17
14
October
8.5
9
8
11
7
November
1.4
3
0
3
4
December
-2.7
2
-1
1
-3
Average
7.3
-1.6
8.8
8.1
8.9
8.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.7
23
3
8
12
10
February
7.8
5
7
13
19
7
March
8.7
4
12
12
12
5
April
5.7
1
3
9
8
May
8.1
10
15
8
9
June
2.8
3
5
5
2
July
3.4
2
5
3
8
August
3.3
3
4
1
2
September
3.5
3
3
2
4
October
6.5
11
4
10
4
November
4.4
4
6
1
5
December
5.7
13
7
1
4
Average
6.3
10.9
5.9
7.0
6.5
5.5
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
9
9
10
10
9
February
10.3
10
10
11
10
9
March
11.1
12
11
11
12
10
April
11.3
12
13
11
10
May
8.9
8
10
8
9
June
8.6
6
9
7
9
July
7.4
8
8
7
7
August
7.5
7
7
9
7
September
8.1
8
8
9
8
October
9.7
10
9
9
10
November
9.7
8
11
10
11
December
9.3
10
9
10
9
Average
9.4
10.2
8.8
9.5
9.2
9.0
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
286°
276°
305°
290°
273°
February
219°
210°
288°
352°
312°
March
206°
315°
295°
159°
180°
April
221°
211°
239°
280°
May
144°
139°
149°
074°
June
140°
180°
179°
179°
July
218°
172°
176°
135°
August
230°
158°
165°
153°
September
156°
157°
182°
181°
October
275°
249°
257°
237°
November
186°
251°
218°
205°
December
243°
197°
201°
278°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.