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
66.6
56
64
85
76
63
February
79.7
88
81
83
80
80
March
85.9
86
82
82
96
83
April
91.1
93
98
94
92
84
May
91.3
97
84
94
95
June
92.3
83
96
95
99
July
93.0
86
94
87
94
August
88.7
86
90
97
70
September
91.8
92
85
97
88
October
86.5
84
90
82
89
November
90.2
92
91
95
91
December
77.6
70
66
83
74
Average
86.4
81.2
85.1
87.6
90.1
84.7
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
0
4
-2
1
3
February
4.3
9
7
2
-3
2
March
9.5
13
8
10
12
10
April
15.5
17
18
13
16
14
May
22.1
23
23
20
20
June
27.8
27
29
28
29
July
28.7
28
29
27
29
August
26.8
27
28
29
21
September
25.5
24
25
27
23
October
17.9
17
19
19
16
November
9.4
11
11
8
13
December
5.1
7
3
7
4
Average
15.3
9.5
16.5
15.9
16.0
15.3
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
-6.3
-6
-3
-11
-5
-3
February
-5.2
-2
-3
-7
-10
-5
March
-1.7
1
-1
-1
1
0
April
4.5
7
4
4
5
3
May
11.0
10
12
9
10
June
16.1
14
16
17
17
July
18.4
17
19
18
18
August
16.2
17
17
18
11
September
14.1
13
13
14
12
October
7.7
9
6
11
5
November
0.5
0
0
-1
3
December
-3.6
1
-3
-2
-3
Average
5.5
-1.9
6.5
5.5
6.4
5.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
15.0
18
26
15
11
12
February
13.6
5
17
18
21
19
March
11.0
9
16
21
7
10
April
9.9
9
8
10
13
13
May
8.1
9
13
9
9
June
4.4
3
5
7
1
July
3.3
5
4
4
3
August
2.5
6
1
1
2
September
4.0
4
1
5
6
October
10.2
12
3
13
14
November
6.9
4
5
6
8
December
9.1
13
13
5
6
Average
8.2
10.3
9.7
8.7
8.1
8.1
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
8.9
9
9
9
8
9
February
9.2
8
11
10
8
9
March
9.9
10
10
10
10
9
April
9.9
11
10
11
9
10
May
8.3
7
9
8
8
June
7.5
7
7
7
8
July
6.1
6
6
6
6
August
6.0
7
6
6
4
September
6.7
6
7
8
7
October
8.2
8
9
7
8
November
9.2
9
11
9
10
December
8.7
8
9
10
8
Average
8.3
9.7
7.9
8.6
8.0
7.8
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
250°
251°
256°
239°
238°
February
246°
245°
245°
272°
271°
March
249°
288°
258°
237°
236°
April
242°
235°
220°
258°
292°
May
031°
173°
236°
021°
June
350°
263°
241°
207°
July
251°
254°
292°
245°
August
288°
236°
195°
255°
September
150°
251°
244°
241°
October
241°
237°
208°
242°
November
243°
231°
242°
234°
December
235°
189°
227°
240°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.