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
89.9
89
92
86
92
97
February
84.0
88
91
86
76
89
March
86.1
87
80
74
94
94
April
82.5
89
62
85
91
May
81.5
98
36
90
98
June
78.9
99
8
99
94
July
80.9
100
0
95
100
August
81.8
100
0
85
100
September
89.4
92
50
90
97
October
88.9
87
91
91
82
November
91.3
95
89
97
95
December
91.0
96
84
84
93
Average
85.3
87.6
93.3
53.8
90.0
95.2
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
4.1
2
3
5
6
4
February
-1.7
5
4
3
-6
4
March
5.5
6
2
9
10
5
April
10.4
11
8
11
11
May
16.3
20
16
15
17
June
22.2
21
22
26
22
July
28.2
28
29
32
27
August
28.2
28
31
26
30
September
22.6
23
24
24
25
October
12.5
13
16
16
5
November
7.5
11
3
12
9
December
4.4
9
-3
2
6
Average
10.8
4.2
14.5
12.7
14.5
14.1
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
-5.3
-5
-4
-7
0
-6
February
-10.8
-5
-5
-8
-14
-3
March
-5.6
-4
-6
-2
-1
-5
April
0.3
1
-2
1
-1
May
5.3
9
4
4
5
June
9.6
10
9
11
10
July
12.6
12
14
16
11
August
12.8
13
16
12
12
September
8.7
9
10
8
8
October
2.0
2
6
5
-5
November
-3.9
1
-7
1
0
December
-6.8
-1
-12
-10
-2
Average
0.2
-5.2
3.3
1.1
2.7
2.5
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
13.2
15
15
14
12
6
February
24.8
19
15
19
36
21
March
15.0
15
20
18
10
17
April
19.9
19
21
23
15
May
8.7
10
3
15
5
June
5.4
4
1
3
13
July
2.3
2
0
3
4
August
3.0
4
0
5
1
September
8.0
7
15
2
5
October
13.2
13
13
8
23
November
13.2
5
25
3
6
December
12.3
5
29
20
2
Average
12.7
16.4
9.7
12.0
10.8
8.7
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
12.0
10
11
14
13
13
February
11.6
10
14
15
10
14
March
9.0
7
8
11
10
11
April
10.7
10
12
10
11
May
8.6
7
11
8
9
June
8.0
6
9
8
9
July
6.9
6
7
7
8
August
7.6
8
7
8
7
September
8.2
7
6
10
8
October
9.6
8
8
11
10
November
12.0
11
11
16
14
December
10.5
10
8
12
8
Average
9.6
8.6
8.5
10.3
10.0
10.0
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
245°
236°
212°
218°
217°
February
243°
244°
222°
224°
224°
March
257°
248°
234°
228°
235°
April
251°
233°
240°
241°
May
355°
241°
256°
235°
June
270°
234°
273°
240°
July
277°
261°
355°
243°
August
259°
355°
254°
251°
September
264°
269°
235°
254°
October
257°
254°
217°
217°
November
242°
244°
221°
217°
December
239°
247°
220°
217°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.