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
73.7
58
74
86
81
61
February
86.2
92
87
94
84
94
March
84.9
91
84
89
85
75
April
89.6
89
98
91
99
86
May
90.6
92
86
91
94
June
96.4
97
98
93
97
July
95.8
96
93
96
94
August
95.2
90
94
100
99
September
91.1
97
89
97
83
October
90.3
93
97
90
94
November
91.8
97
89
98
89
December
84.2
74
71
90
88
Average
88.8
82.2
90.3
90.5
92.2
88.2
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
0.6
-2
2
0
2
1
February
4.8
12
7
5
-3
4
March
11.1
14
10
11
13
13
April
17.2
19
19
16
19
16
May
22.6
25
23
21
20
June
28.8
29
29
29
29
July
29.8
29
31
29
30
August
28.8
28
30
29
29
September
26.2
27
26
27
24
October
17.5
19
19
19
16
November
10.1
12
10
12
14
December
5.8
7
4
9
5
Average
16.1
10.7
17.8
17.4
17.2
16.7
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
-8.6
-9
-5
-11
-5
-6
February
-7.8
-1
-5
-9
-12
-6
March
0.5
2
-1
-1
3
2
April
5.3
7
5
4
7
4
May
12.4
12
13
12
11
June
17.9
17
18
18
19
July
19.7
19
20
19
21
August
18.3
19
19
20
18
September
14.9
15
14
15
13
October
7.1
8
6
10
5
November
-1.8
1
-1
1
2
December
-4.6
0
-5
-2
-5
Average
5.7
-1.8
7.1
6.1
7.3
6.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.0
19
6
3
10
16
February
6.7
2
11
7
14
4
March
7.7
6
8
9
8
7
April
6.9
7
2
11
5
7
May
4.8
4
7
5
4
June
2.3
2
1
4
3
July
3.2
5
3
4
6
August
2.7
3
6
2
1
September
4.3
1
6
1
10
October
9.0
9
14
10
3
November
9.4
4
24
4
18
December
6.3
13
9
1
4
Average
6.1
8.5
5.4
7.9
5.3
6.4
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
9.6
9
9
10
9
10
February
10.2
10
11
12
9
10
March
10.5
11
10
11
11
9
April
11.2
12
12
12
11
10
May
8.4
7
9
9
9
June
7.6
6
8
7
8
July
6.6
6
7
6
6
August
6.7
6
7
7
7
September
7.6
7
8
8
8
October
9.2
10
9
8
9
November
9.9
9
11
10
11
December
9.5
9
10
10
9
Average
9.0
10.4
8.4
9.4
8.6
8.7
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
302°
296°
294°
318°
285°
February
266°
264°
292°
332°
322°
March
314°
321°
323°
186°
239°
April
270°
261°
244°
235°
288°
May
135°
165°
184°
339°
June
308°
210°
223°
181°
July
288°
228°
222°
169°
August
224°
210°
177°
191°
September
190°
211°
211°
214°
October
291°
265°
332°
287°
November
237°
265°
251°
223°
December
256°
227°
233°
295°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.