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
72.0
62
60
86
72
63
February
82.1
84
80
63
85
95
March
85.6
87
79
85
95
88
April
84.2
89
79
68
84
97
May
93.1
92
93
95
93
June
93.8
88
90
100
98
July
95.3
97
94
88
98
August
91.8
94
85
92
93
September
88.1
85
87
97
94
October
88.3
88
93
88
90
November
85.9
90
74
90
90
December
71.6
52
60
78
80
Average
86.5
81.2
83.2
82.9
89.4
90.9
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
-7.2
-6
-6
-10
-4
-7
February
-6.8
3
-3
-10
-10
-4
March
2.7
4
0
1
8
4
April
9.6
13
8
5
11
10
May
19.9
23
19
20
18
June
25.9
27
26
29
26
July
27.3
27
27
29
28
August
25.3
27
25
27
26
September
21.2
23
22
23
19
October
11.4
13
14
16
7
November
2.2
4
2
3
6
December
-4.6
2
-5
-4
-2
Average
9.9
3.2
12.1
10.4
12.5
10.9
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
-17.5
-13
-14
-23
-11
-16
February
-17.2
-7
-16
-23
-21
-17
March
-9.9
-7
-12
-9
-4
-6
April
-2.7
1
-2
-2
0
-3
May
6.8
9
7
6
6
June
13.3
15
13
14
14
July
14.9
13
15
16
16
August
13.8
15
12
15
15
September
10.2
13
10
10
8
October
2.1
4
2
6
-1
November
-7.6
-5
-6
-5
-5
December
-13.8
-4
-13
-14
-12
Average
-1.2
-7.4
1.2
-1.3
1.1
-1.9
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
10.7
14
14
10
7
12
February
13.5
7
14
34
4
6
March
10.6
16
23
10
4
3
April
14.9
18
20
31
14
6
May
8.4
5
7
13
5
June
4.4
7
2
5
6
July
3.4
3
2
2
5
August
4.0
1
3
5
3
September
6.0
8
4
5
7
October
8.9
9
7
10
11
November
10.5
6
25
8
5
December
16.5
20
31
18
9
Average
9.3
14.1
10.3
12.4
7.6
6.2
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
7
8
February
8.7
9
8
12
8
8
March
9.3
10
9
10
10
9
April
9.7
10
10
11
9
10
May
9.0
9
11
9
9
June
9.0
7
10
8
10
July
7.4
7
8
7
8
August
7.9
8
7
10
8
September
8.8
8
8
9
9
October
9.5
9
9
8
10
November
9.5
10
9
9
9
December
7.9
8
9
8
8
Average
8.8
9.4
8.2
9.4
8.5
8.8
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
270°
291°
283°
284°
249°
February
281°
264°
304°
265°
276°
March
323°
010°
315°
187°
252°
April
331°
346°
346°
328°
307°
May
148°
220°
215°
032°
June
124°
254°
263°
179°
July
301°
277°
219°
233°
August
099°
225°
222°
192°
September
130°
207°
230°
267°
October
303°
268°
159°
276°
November
273°
284°
265°
243°
December
264°
133°
261°
271°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.