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
69.0
66
66
84
73
68
February
82.3
83
87
80
81
92
March
88.9
91
82
95
95
85
April
85.8
93
83
79
79
96
May
95.3
95
95
97
94
June
98.8
99
100
98
97
July
97.8
98
98
100
98
August
93.5
95
95
94
95
September
92.4
85
95
95
98
October
88.8
87
99
84
91
November
86.9
96
83
88
91
December
72.6
63
64
85
81
Average
86.6
84.4
87.6
90.5
88.9
90.8
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
-7.4
-5
-6
-10
-4
-7
February
-7.9
4
-5
-8
-11
-5
March
2.2
6
-1
1
8
4
April
9.5
14
8
6
11
10
May
19.3
25
19
21
17
June
26.4
29
27
26
27
July
26.5
28
27
27
28
August
25.6
28
26
27
26
September
22.0
24
23
24
21
October
12.3
14
15
16
8
November
3.1
7
2
5
7
December
-3.4
3
-4
-4
-1
Average
9.0
4.7
12.2
10.8
11.1
9.8
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
-15.5
-12
-15
-21
-11
-15
February
-17.8
-5
-16
-20
-18
-16
March
-7.5
-4
-12
-7
-2
-4
April
0.1
3
-2
-1
1
0
May
8.3
10
8
8
8
June
15.5
17
15
15
16
July
16.4
15
17
17
19
August
15.4
16
16
16
16
September
12.1
15
11
12
9
October
3.3
5
3
7
-1
November
-5.1
-3
-5
-4
-3
December
-11.3
-3
-12
-13
-10
Average
-1.9
-5.4
1.5
0.8
1.2
0.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
11.0
7
20
8
12
18
February
8.8
3
6
10
7
7
March
8.2
12
14
3
8
3
April
12.6
14
10
22
13
5
May
5.0
1
3
3
8
June
2.0
2
1
3
3
July
3.8
4
3
4
2
August
3.2
3
3
4
3
September
4.3
5
3
7
2
October
7.8
7
3
9
7
November
7.2
4
15
3
1
December
12.2
14
20
16
10
Average
7.5
9.2
7.1
6.9
7.4
5.3
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
8.6
9
7
10
8
9
February
9.5
10
10
12
9
9
March
10.1
11
10
10
10
10
April
10.9
12
10
14
10
9
May
9.9
11
10
10
10
June
9.0
8
10
6
11
July
6.7
7
7
6
8
August
7.6
7
7
8
8
September
8.3
8
8
9
8
October
9.7
9
10
8
10
November
10.3
10
11
10
11
December
9.3
8
11
9
10
Average
9.3
10.6
8.8
9.9
8.7
9.4
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
288°
311°
296°
296°
321°
February
280°
159°
304°
269°
270°
March
342°
024°
340°
152°
229°
April
359°
004°
002°
322°
296°
May
136°
203°
180°
009°
June
127°
234°
089°
140°
July
311°
241°
142°
158°
August
124°
166°
173°
158°
September
132°
169°
200°
210°
October
299°
248°
157°
292°
November
275°
293°
261°
230°
December
258°
143°
263°
293°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.