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
89.1
57
February
90.2
87
88
March
86.3
72
88
89
68
April
78.3
65
87
75
76
May
87.2
96
83
73
100
June
87.6
82
87
80
July
84.0
76
93
91
August
89.1
85
84
96
September
92.5
86
94
95
October
91.6
72
96
99
November
75.9
75
70
December
87.3
73
30
Average
85.1
65.3
89.8
78.3
84.9
90.2
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
2.2
1
February
4.0
4
1
March
3.7
4
0
3
0
April
5.1
4
4
4
6
May
8.6
7
9
9
15
June
12.3
13
12
12
July
15.2
15
15
16
August
15.7
15
15
16
September
13.3
12
12
13
October
9.1
8
8
10
November
4.9
6
-1
December
3.0
7
-4
Average
7.8
4.2
5.2
9.2
8.3
11.8
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
-2.8
-1
February
0.3
1
-3
March
-1.5
-2
-2
-2
-6
April
0.8
0
-2
2
2
May
4.3
3
5
5
10
June
8.1
9
8
8
July
10.9
11
11
12
August
10.9
11
10
11
September
8.7
9
8
8
October
5.3
5
5
5
November
1.8
2
-4
December
-1.2
2
-6
Average
3.5
-1.4
-1.9
5.9
4.3
7.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
35.9
29
February
35.2
32
31
March
32.3
60
17
33
73
April
46.3
61
43
55
33
May
30.3
42
12
31
5
June
27.0
20
27
36
July
18.0
14
10
10
August
17.9
34
21
14
September
23.4
28
23
20
October
41.1
72
36
24
November
58.1
59
61
December
43.2
30
70
Average
37.1
60.6
42.6
39.1
27.0
23.1
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
9.3
8
February
8.4
8
9
March
9.0
9
12
10
16
April
8.6
9
11
11
8
May
7.3
9
7
8
7
June
6.2
5
7
7
July
5.6
5
6
6
August
6.3
6
7
6
September
7.4
5
8
8
October
8.9
15
10
6
November
8.7
8
14
December
9.5
9
17
Average
7.9
8.6
10.0
8.0
7.8
6.9
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
129°
February
118°
241°
March
181°
248°
238°
244°
April
251°
244°
107°
284°
May
227°
296°
070°
241°
June
112°
090°
021°
July
277°
251°
264°
August
287°
239°
253°
September
227°
249°
241°
October
243°
234°
234°
November
218°
247°
December
164°
252°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.