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
73.2
68
75
70
81
79
February
78.4
90
83
67
75
77
March
84.1
74
83
83
96
88
April
90.0
97
90
91
92
May
91.8
96
90
96
94
June
92.5
83
95
95
99
July
95.0
94
95
93
95
August
95.3
93
95
97
95
September
94.2
93
93
98
91
October
91.0
91
99
82
94
November
90.1
94
80
91
99
December
79.2
72
72
89
85
Average
87.4
76.9
88.4
87.0
91.2
91.3
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
-1.6
1
2
-3
-1
2
February
1.9
5
3
1
-2
1
March
5.4
9
4
6
8
8
April
12.1
15
13
13
10
May
18.9
19
22
18
18
June
23.7
24
24
26
25
July
26.7
27
27
25
29
August
25.8
24
28
27
26
September
22.0
23
21
22
22
October
15.7
17
16
16
15
November
7.8
8
10
8
12
December
2.6
6
2
5
3
Average
12.4
4.7
14.3
14.2
13.7
14.0
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
-10.4
-7
-5
-18
-9
-6
February
-9.8
-5
-8
-11
-12
-8
March
-5.7
-1
-4
-4
-4
-2
April
1.8
3
2
3
1
May
7.3
6
9
7
6
June
13.0
13
13
15
13
July
16.6
17
16
15
19
August
15.7
15
16
18
15
September
11.0
11
12
12
9
October
6.0
8
4
8
4
November
-1.3
-1
1
0
2
December
-6.5
-1
-4
-3
-4
Average
2.6
-5.7
4.4
3.1
4.2
4.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
24.2
33
30
26
13
18
February
21.9
12
25
34
26
16
March
18.3
19
26
23
9
17
April
14.9
10
18
16
13
May
10.5
10
12
6
6
June
8.0
10
8
7
1
July
5.7
6
6
8
3
August
5.8
9
9
6
6
September
5.6
5
8
9
5
October
15.5
21
9
14
18
November
15.8
15
21
17
9
December
22.6
26
32
13
25
Average
14.1
21.2
15.0
15.9
11.0
10.3
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
7.8
8
7
8
6
7
February
9.0
8
10
10
8
9
March
8.7
9
9
8
10
8
April
8.9
8
9
8
10
May
7.2
7
7
7
8
June
7.0
6
7
8
7
July
6.6
6
7
6
7
August
6.2
6
6
6
6
September
6.2
6
6
6
7
October
7.4
7
7
6
8
November
8.2
8
9
7
9
December
7.5
6
8
8
9
Average
7.6
8.4
7.1
7.6
7.1
7.9
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
258°
301°
288°
319°
260°
February
239°
242°
249°
261°
248°
March
253°
275°
250°
247°
230°
April
243°
243°
274°
261°
May
266°
272°
255°
259°
June
333°
243°
233°
247°
July
240°
243°
320°
241°
August
249°
249°
243°
254°
September
275°
293°
225°
230°
October
242°
220°
001°
228°
November
247°
241°
248°
233°
December
294°
343°
230°
246°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.