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
75.0
69
65
74
83
73
February
87.2
69
91
86
87
95
March
91.4
97
85
96
95
April
93.6
88
88
90
98
May
92.9
90
82
93
98
June
96.3
90
93
97
98
July
95.2
92
98
85
99
August
94.0
91
94
88
97
September
93.0
84
93
100
99
October
89.0
82
88
89
95
November
83.3
79
85
90
92
December
84.7
88
58
86
95
Average
88.1
68.7
86.9
87.1
90.7
95.0
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
-10.2
-9
-10
-13
-6
-10
February
-10.7
-3
-8
-14
-11
-9
March
-1.2
-6
-3
5
1
April
7.3
5
4
10
7
May
18.2
22
15
18
16
June
25.2
27
23
27
25
July
26.2
24
25
28
27
August
25.0
25
26
24
27
September
19.6
22
21
23
19
October
9.7
10
11
14
7
November
-1.6
2
0
2
2
December
-5.7
1
-9
-5
0
Average
7.5
-6.3
9.6
7.9
11.4
9.8
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
-16.3
-14
-16
-19
-12
-16
February
-18.6
-9
-18
-23
-19
-18
March
-10.3
-16
-10
-7
-8
April
-3.9
-2
-3
-2
-2
May
6.3
9
7
4
6
June
13.7
16
13
15
14
July
15.5
13
16
16
16
August
13.6
15
16
14
14
September
9.2
10
10
10
8
October
1.4
3
2
5
-1
November
-7.3
-5
-6
-5
-6
December
-11.0
-7
-14
-11
-7
Average
-2.7
-12.7
0.3
-1.8
1.2
0.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
42.0
56
47
38
26
53
February
27.8
31
15
33
28
25
March
14.8
15
22
8
11
April
12.1
17
15
13
14
May
11.1
10
26
11
8
June
6.2
5
11
6
6
July
5.6
6
10
3
4
August
6.7
9
6
10
5
September
11.6
13
11
4
8
October
16.0
23
15
11
18
November
28.2
25
33
17
16
December
22.6
8
51
13
12
Average
18.7
41.7
15.4
20.2
11.4
13.6
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
9.9
11
8
11
10
9
February
10.4
11
11
11
11
10
March
10.4
10
11
11
11
April
10.8
10
12
12
11
May
10.2
10
12
10
11
June
9.0
8
10
9
10
July
9.1
8
9
8
10
August
8.8
9
9
10
9
September
10.0
9
10
11
11
October
11.0
10
11
11
12
November
10.7
12
11
11
10
December
10.0
10
10
12
8
Average
10.0
10.5
9.3
10.6
10.2
10.2
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
277°
314°
304°
278°
208°
February
340°
291°
298°
254°
271°
March
297°
290°
270°
243°
April
020°
007°
328°
305°
May
020°
165°
302°
263°
June
009°
283°
283°
273°
July
301°
295°
214°
223°
August
292°
287°
295°
232°
September
205°
291°
228°
268°
October
317°
291°
194°
286°
November
281°
289°
242°
229°
December
218°
008°
263°
253°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.