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
75.7
68
64
76
84
80
February
87.3
81
88
85
90
86
March
84.5
92
89
87
93
88
April
90.0
89
86
99
98
May
95.4
92
96
97
96
June
92.3
84
94
97
91
July
92.4
85
93
88
97
August
93.4
95
93
99
94
September
90.2
85
96
99
97
October
92.8
90
97
94
95
November
75.0
83
72
91
65
December
84.9
98
67
81
88
Average
87.7
80.6
86.9
88.2
93.2
90.5
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
-9.9
-12
-7
-7
-6
-11
February
-9.6
-3
-7
-8
-13
-4
March
-2.7
-3
-5
-1
5
-3
April
8.1
8
7
12
5
May
19.1
24
17
17
17
June
22.1
24
21
25
20
July
23.9
23
24
26
23
August
23.2
24
26
24
23
September
18.0
20
22
21
18
October
9.5
10
15
11
5
November
-2.2
3
-5
1
-2
December
-7.5
0
-13
-13
-3
Average
6.5
-6.2
9.9
9.0
9.3
7.4
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
-16.0
-19
-13
-17
-13
-18
February
-18.6
-12
-15
-18
-21
-14
March
-12.9
-13
-14
-9
-7
-13
April
-4.4
-3
-4
-3
-6
May
5.1
8
4
3
4
June
10.2
12
9
12
9
July
12.0
12
13
13
13
August
10.9
11
13
11
11
September
5.8
7
7
7
6
October
-2.5
-1
2
-1
-3
November
-10.9
-6
-12
-8
-9
December
-14.0
-8
-22
-20
-11
Average
-4.2
-15.7
-1.2
-3.9
-3.8
-3.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
29.0
24
22
34
33
33
February
31.9
22
25
32
36
30
March
19.8
18
25
26
6
20
April
13.0
16
21
1
9
May
7.0
2
9
5
11
June
10.5
7
11
7
17
July
5.8
4
8
1
11
August
5.6
6
5
7
5
September
8.5
2
2
5
6
October
9.6
13
2
1
15
November
27.0
8
34
15
30
December
22.7
0
58
34
17
Average
15.6
21.4
10.3
17.5
10.8
15.9
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
8
8
10
10
9
February
9.4
9
10
10
9
10
March
9.9
10
9
11
10
11
April
10.6
10
12
10
12
May
10.2
10
11
10
11
June
9.4
8
9
10
10
July
8.5
9
8
8
10
August
9.0
9
9
9
11
September
9.6
8
10
11
11
October
10.4
11
10
11
11
November
9.7
10
10
10
10
December
9.2
8
10
9
9
Average
9.5
8.9
9.1
10.0
9.8
10.3
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
301°
253°
274°
255°
270°
February
294°
257°
274°
286°
268°
March
141°
155°
313°
253°
289°
April
145°
035°
298°
284°
May
129°
303°
251°
158°
June
211°
019°
274°
343°
July
306°
302°
284°
272°
August
296°
278°
277°
268°
September
253°
271°
264°
284°
October
246°
267°
184°
291°
November
247°
309°
253°
277°
December
228°
295°
278°
270°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.