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
79.8
85
63
77
89
80
February
88.4
75
81
89
94
96
March
88.7
84
92
83
92
94
April
96.1
94
95
97
97
May
92.6
81
92
94
99
June
90.0
93
96
82
91
July
86.1
89
92
88
57
August
88.8
77
93
91
84
September
92.8
87
92
99
99
October
89.2
77
92
93
94
November
81.8
84
68
86
83
December
89.7
93
82
86
95
Average
88.4
81.2
83.9
87.9
90.9
88.7
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
-11.3
-11
-10
-13
-7
-10
February
-11.4
-4
-9
-14
-15
-7
March
-3.2
-3
-6
-3
1
-3
April
6.5
6
4
10
4
May
18.9
25
17
18
17
June
22.7
26
22
25
21
July
24.7
24
25
28
25
August
23.9
24
26
24
24
September
19.1
23
22
22
18
October
8.2
9
10
11
5
November
-4.7
1
-5
-1
-3
December
-9.0
-2
-14
-15
-6
Average
5.7
-6.1
9.3
7.1
8.6
6.9
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
-20.5
-17
-18
-24
-17
-19
February
-22.6
-13
-22
-26
-25
-19
March
-15.8
-14
-20
-15
-10
-15
April
-5.3
-5
-5
-3
-8
May
4.1
7
4
2
3
June
10.4
12
10
12
9
July
12.1
10
12
13
13
August
10.7
12
12
11
11
September
5.9
7
7
7
5
October
-2.7
-1
1
0
-2
November
-11.3
-6
-12
-9
-12
December
-18.6
-10
-21
-23
-15
Average
-6.8
-15.2
-3.4
-5.9
-4.7
-4.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
33.7
41
48
41
25
17
February
18.7
20
30
31
15
14
March
15.6
17
18
25
9
15
April
9.9
15
17
7
10
May
9.2
13
18
7
6
June
7.5
2
14
3
15
July
5.5
9
11
1
6
August
5.7
13
9
7
2
September
5.4
4
8
2
6
October
10.8
22
7
4
12
November
31.2
30
51
13
32
December
20.2
15
35
34
13
Average
14.2
25.5
17.6
21.1
9.1
11.4
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
7.6
8
6
9
8
8
February
8.3
8
9
8
8
9
March
8.3
9
7
9
9
9
April
9.4
10
10
10
9
May
9.9
9
12
10
10
June
8.9
8
10
9
10
July
7.5
8
7
8
7
August
8.1
8
7
8
9
September
9.0
8
9
10
10
October
9.4
8
10
9
11
November
8.9
9
11
8
9
December
7.8
8
9
8
7
Average
8.6
8.4
8.0
9.2
8.7
9.0
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
276°
245°
305°
216°
256°
February
316°
247°
276°
247°
237°
March
323°
208°
290°
174°
295°
April
059°
345°
302°
253°
May
022°
346°
331°
213°
June
157°
328°
261°
007°
July
304°
268°
253°
204°
August
289°
236°
273°
227°
September
208°
233°
243°
263°
October
292°
277°
257°
264°
November
251°
325°
214°
279°
December
238°
315°
255°
227°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.