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
76.3
66
59
75
86
73
February
88.3
75
87
81
92
93
March
86.4
78
90
81
88
93
April
91.7
84
83
93
97
May
95.2
87
87
95
100
June
96.3
97
91
99
95
July
95.1
93
91
92
96
August
91.0
79
91
91
91
September
93.6
83
93
99
99
October
89.7
80
88
93
93
November
80.0
81
73
83
82
December
86.7
92
84
83
83
Average
88.4
72.7
84.0
84.7
91.6
92.3
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
-10.7
-10
-9
-11
-6
-10
February
-10.5
-3
-8
-11
-14
-5
March
-2.1
-4
-6
-2
4
-1
April
7.7
5
3
12
7
May
19.2
23
16
18
18
June
23.8
26
20
26
23
July
26.2
24
25
29
27
August
25.0
25
26
24
26
September
19.5
22
21
23
18
October
9.6
9
12
14
6
November
-1.0
1
-3
2
1
December
-7.1
0
-13
-12
-3
Average
6.7
-6.0
9.4
6.8
10.0
9.0
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
-18.4
-16
-17
-21
-15
-17
February
-20.8
-12
-18
-23
-24
-17
March
-12.1
-14
-18
-11
-7
-11
April
-4.1
-5
-4
-2
-5
May
4.7
8
6
3
4
June
11.2
14
8
13
11
July
13.0
10
14
15
14
August
11.4
12
13
12
11
September
7.0
9
8
9
6
October
-1.1
0
0
2
-3
November
-10.9
-5
-12
-7
-9
December
-16.8
-9
-20
-20
-13
Average
-5.9
-15.8
-2.4
-4.4
-2.1
-3.6
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
25.9
43
33
31
17
19
February
16.4
24
23
28
6
13
March
14.3
26
8
24
9
15
April
12.9
21
26
9
10
May
6.8
5
27
6
2
June
5.9
4
13
1
6
July
4.0
5
12
2
2
August
4.8
13
4
6
3
September
5.5
5
5
2
6
October
10.8
23
7
7
15
November
25.9
27
45
15
24
December
17.4
7
26
20
22
Average
13.4
31.2
14.2
20.7
7.6
10.3
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
9.4
11
7
12
9
9
February
9.8
11
10
11
10
10
March
9.9
10
8
11
11
10
April
11.3
12
13
11
12
May
10.3
9
14
10
10
June
9.8
8
10
10
12
July
8.8
8
8
8
10
August
8.6
8
8
9
9
September
9.7
9
10
11
11
October
10.7
10
11
10
12
November
9.7
10
11
10
10
December
9.1
9
10
11
8
Average
9.8
10.3
8.9
10.6
10.1
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
296°
244°
286°
227°
233°
February
307°
273°
283°
267°
246°
March
317°
271°
289°
207°
262°
April
039°
017°
313°
300°
May
073°
006°
270°
191°
June
173°
341°
274°
241°
July
303°
291°
208°
244°
August
281°
250°
285°
251°
September
210°
264°
266°
283°
October
321°
302°
234°
278°
November
261°
295°
226°
244°
December
245°
309°
256°
260°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.