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
77.3
63
89
92
74
75
February
84.6
95
100
85
92
72
March
87.3
93
84
93
91
80
April
92.8
96
95
92
90
May
93.0
99
91
92
96
June
95.7
93
98
96
98
July
90.8
74
94
92
94
August
93.2
93
91
95
96
September
92.0
94
92
93
88
October
88.1
91
95
79
91
November
89.4
91
88
93
93
December
83.9
76
96
77
92
Average
89.0
84.4
90.1
92.4
89.5
89.8
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
1.1
-1
3
0
1
4
February
4.5
9
8
3
-2
4
March
9.9
13
9
11
13
11
April
15.8
18
15
16
15
May
21.7
23
23
21
20
June
26.7
26
27
27
28
July
26.1
24
28
21
28
August
26.5
26
26
28
26
September
24.6
24
24
26
23
October
17.2
18
17
19
16
November
9.0
11
10
8
13
December
5.2
7
6
8
4
Average
14.4
7.0
16.7
16.5
15.7
16.1
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
-7.8
-6
-3
-10
-5
-3
February
-5.0
-2
-3
-8
-9
-4
March
-1.8
2
-1
0
1
2
April
4.1
3
4
4
3
May
9.9
10
12
8
10
June
14.6
11
15
17
16
July
15.4
14
17
12
16
August
15.0
16
15
16
12
September
11.6
12
12
13
5
October
5.6
7
4
10
2
November
-1.3
-1
0
-1
2
December
-4.8
0
-5
-1
-4
Average
4.0
-3.8
5.5
5.5
5.4
4.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.6
9
12
6
12
7
February
10.1
4
6
18
13
18
March
7.9
3
10
8
5
10
April
7.1
5
7
7
7
May
6.5
3
9
9
5
June
3.6
3
3
6
1
July
4.3
1
7
4
4
August
2.4
2
2
4
2
September
4.3
3
2
6
2
October
6.1
5
4
9
4
November
4.9
3
9
3
2
December
6.0
5
0
8
5
Average
5.9
5.0
4.4
6.5
7.0
5.3
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
7.0
7
9
6
7
8
February
7.7
8
10
6
6
9
March
9.5
11
11
9
8
10
April
9.3
9
11
8
9
May
7.6
7
9
5
8
June
6.5
7
6
5
7
July
4.4
5
6
1
4
August
4.3
5
5
3
4
September
5.1
4
6
5
6
October
7.2
8
9
4
7
November
8.2
8
9
6
9
December
6.9
7
9
6
8
Average
7.2
8.8
7.3
7.3
5.2
7.2
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
245°
263°
265°
211°
227°
February
256°
226°
240°
309°
269°
March
232°
238°
228°
202°
243°
April
222°
215°
235°
255°
May
074°
168°
195°
206°
June
014°
234°
217°
199°
July
240°
239°
235°
231°
August
237°
220°
190°
260°
September
167°
267°
228°
205°
October
232°
220°
212°
212°
November
237°
213°
239°
222°
December
242°
206°
221°
225°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.