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
84.9
71
94
91
94
77
February
90.4
81
93
97
86
95
March
88.6
88
84
92
96
83
April
94.9
97
95
92
98
94
May
94.5
90
96
96
98
June
96.9
97
97
98
96
July
98.0
96
100
99
98
August
94.8
90
98
92
100
September
80.0
86
80
78
74
October
94.4
94
96
95
93
November
86.4
91
77
92
88
December
79.3
79
70
73
91
Average
90.1
84.5
90.9
91.6
92.2
91.4
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
4.8
4
5
7
5
4
February
6.4
6
6
9
4
7
March
7.6
8
4
12
9
7
April
12.2
13
12
10
14
13
May
16.8
19
15
18
17
June
21.4
22
20
24
20
July
28.1
29
29
29
27
August
27.5
27
29
27
27
September
23.1
20
24
24
25
October
16.8
16
19
14
18
November
7.3
9
5
9
6
December
3.8
6
0
4
5
Average
13.5
7.6
14.4
15.2
15.2
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
-5.7
-3
-6
-6
-3
-2
February
-6.9
-3
-6
-7
-4
-5
March
-4.2
-4
-6
-2
-4
-3
April
-2.2
-2
-1
-3
-2
-1
May
1.6
3
1
1
2
June
5.1
4
5
7
4
July
6.2
6
7
7
6
August
7.4
8
8
6
8
September
3.0
3
4
2
3
October
-1.7
-1
-1
0
0
November
-3.0
-3
-6
0
-4
December
-5.8
-2
-10
-2
-4
Average
-1.5
-3.0
-1.9
-1.6
0.6
0.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
19.0
30
22
7
5
28
February
12.9
20
17
6
18
4
March
16.7
24
29
5
1
19
April
8.3
7
14
11
1
6
May
3.2
4
5
2
3
June
1.9
0
4
2
2
July
0.4
0
1
1
0
August
0.4
1
1
0
0
September
2.6
5
1
3
0
October
3.0
6
1
2
3
November
12.9
9
23
8
9
December
17.3
19
24
19
10
Average
9.1
20.0
9.6
6.4
4.2
5.4
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
8.8
9
10
8
9
9
February
8.3
8
9
8
9
8
March
8.9
9
9
8
9
9
April
8.7
8
10
9
9
7
May
7.5
7
8
7
7
June
6.8
6
7
7
8
July
5.6
5
6
6
6
August
5.8
6
5
6
6
September
6.8
7
6
7
8
October
7.6
7
8
9
8
November
8.2
8
9
8
8
December
8.1
8
8
9
7
Average
7.7
8.4
7.5
7.3
7.7
7.5
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
211°
196°
202°
211°
211°
February
212°
209°
206°
225°
214°
March
216°
209°
223°
212°
233°
April
239°
217°
228°
254°
246°
May
172°
232°
301°
226°
June
338°
231°
234°
245°
July
215°
217°
237°
210°
August
208°
187°
312°
202°
September
212°
202°
203°
209°
October
202°
191°
213°
209°
November
205°
192°
210°
200°
December
208°
197°
208°
199°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.