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
61.1
55
52
66
56
74
February
71.0
83
56
63
75
74
March
78.4
72
70
76
91
91
April
85.5
82
89
81
85
92
May
90.5
92
89
94
93
June
89.7
77
89
95
92
July
87.7
79
85
82
90
August
88.6
78
88
90
93
September
84.4
76
73
90
91
October
85.2
80
94
78
89
November
78.2
77
70
88
90
December
70.4
54
71
81
67
Average
81.4
72.8
74.4
79.7
84.9
87.4
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
-4.9
-3
-1
-6
-4
-1
February
-1.4
2
0
-1
-3
-2
March
3.1
6
2
4
5
5
April
10.3
11
14
10
12
8
May
17.8
18
21
17
17
June
21.9
22
22
24
23
July
24.8
25
24
22
27
August
23.5
22
25
25
23
September
19.8
21
18
19
19
October
13.7
14
15
15
12
November
4.5
4
8
5
9
December
-1.8
2
1
2
0
Average
10.4
3.6
11.9
12.1
11.5
11.6
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
-13.3
-9
-8
-21
-12
-11
February
-13.7
-10
-13
-15
-15
-13
March
-9.5
-5
-8
-8
-9
-6
April
-2.3
-1
0
-1
-2
-3
May
3.4
1
5
3
3
June
8.7
9
9
10
8
July
12.2
13
12
12
14
August
11.1
11
12
14
11
September
7.1
8
8
7
5
October
2.4
4
-1
5
1
November
-6.8
-5
-3
-5
-4
December
-10.9
-5
-6
-8
-8
Average
-2.8
-7.4
0.6
-1.5
0.1
-1.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
27.2
33
31
29
23
26
February
26.0
14
30
35
29
27
March
21.6
22
32
20
12
16
April
17.4
22
13
20
18
16
May
9.3
7
8
5
7
June
7.6
11
8
4
5
July
5.1
8
5
9
4
August
6.2
10
6
8
8
September
6.0
4
11
6
4
October
12.6
16
6
13
17
November
21.8
19
25
17
13
December
25.4
25
37
14
27
Average
15.2
22.7
16.0
15.9
11.9
12.8
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
5.6
6
5
6
4
6
February
6.9
6
7
8
6
7
March
6.5
6
6
7
7
7
April
6.6
7
6
6
6
8
May
5.8
6
6
6
6
June
5.7
4
6
7
6
July
5.1
4
6
5
5
August
4.8
4
5
5
5
September
4.9
4
4
6
7
October
5.9
5
6
5
6
November
6.1
6
7
5
7
December
5.5
4
6
6
7
Average
5.8
6.1
5.0
5.9
5.6
6.3
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
231°
241°
234°
237°
238°
February
227°
230°
231°
229°
235°
March
248°
238°
237°
239°
222°
April
093°
224°
245°
301°
234°
May
270°
193°
261°
246°
June
058°
235°
230°
236°
July
225°
234°
241°
236°
August
226°
232°
231°
237°
September
208°
240°
219°
221°
October
221°
198°
161°
227°
November
233°
230°
233°
232°
December
237°
224°
229°
225°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.