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
82.7
82
63
84
81
84
February
89.3
76
94
94
89
94
March
85.8
89
75
85
89
89
April
92.3
87
89
99
98
May
95.3
90
96
95
98
June
94.9
89
96
98
92
July
92.8
85
90
88
97
August
94.6
93
97
96
100
September
92.4
86
97
99
97
October
94.9
93
96
97
99
November
80.0
84
74
92
74
December
90.3
96
76
93
90
Average
90.0
82.5
86.2
90.5
93.3
93.2
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
-8.9
-11
-6
-7
-6
-9
February
-9.8
-3
-7
-6
-13
-3
March
-1.9
-2
-6
1
4
1
April
9.9
8
9
14
8
May
20.4
24
19
18
19
June
24.4
27
23
27
23
July
26.6
27
26
30
24
August
26.8
27
29
26
27
September
20.9
23
25
23
21
October
11.4
11
16
14
8
November
-1.4
4
-5
4
-1
December
-6.5
3
-13
-11
-5
Average
8.2
-6.6
11.2
10.6
10.8
9.5
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
-17.8
-20
-15
-17
-14
-18
February
-19.6
-14
-16
-17
-23
-15
March
-11.4
-12
-16
-9
-7
-10
April
-4.4
-4
-4
-3
-4
May
4.7
8
4
3
4
June
10.1
11
10
11
10
July
11.6
11
12
13
11
August
10.5
11
12
11
10
September
6.0
7
7
6
6
October
-2.0
-2
1
-1
-3
November
-10.5
-6
-13
-8
-10
December
-15.5
-8
-22
-20
-14
Average
-5.9
-15.1
-2.4
-3.6
-3.5
-3.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
14.5
20
3
20
10
16
February
17.6
25
9
22
11
8
March
11.8
8
23
15
6
12
April
7.7
12
16
2
8
May
5.2
4
6
7
4
June
6.6
5
8
4
8
July
4.2
8
3
2
4
August
3.4
4
1
5
1
September
6.0
6
4
2
6
October
6.1
8
3
1
10
November
16.3
12
16
6
17
December
10.0
3
30
13
6
Average
9.6
17.4
8.1
10.5
5.4
7.8
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
9
8
11
12
10
February
9.9
9
10
11
11
11
March
11.4
10
10
13
11
12
April
12.2
10
13
11
13
May
11.7
10
12
11
13
June
11.5
10
11
10
12
July
9.5
9
8
8
11
August
9.4
9
8
9
11
September
10.8
9
10
12
13
October
11.8
11
10
11
12
November
11.1
10
12
10
12
December
9.9
9
10
10
9
Average
10.7
9.5
9.6
10.8
10.4
11.7
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°
267°
280°
247°
265°
February
296°
252°
280°
275°
251°
March
133°
128°
288°
245°
283°
April
182°
299°
298°
294°
May
126°
293°
232°
225°
June
227°
332°
276°
278°
July
301°
307°
360°
256°
August
290°
265°
258°
264°
September
255°
237°
262°
272°
October
255°
273°
201°
277°
November
248°
298°
238°
264°
December
229°
310°
273°
258°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.