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
76.8
71
52
79
91
82
February
76.6
67
64
77
79
90
March
90.1
99
85
89
97
93
April
95.8
95
91
100
96
May
94.2
90
91
94
96
June
94.6
96
90
94
91
July
86.4
71
80
93
90
August
80.9
89
79
88
85
September
78.3
68
71
89
74
October
83.5
85
70
84
73
November
78.3
77
60
88
81
December
73.4
63
52
76
82
Average
84.8
78.5
78.2
78.4
90.1
86.7
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
-1.0
-3
1
-2
2
-2
February
-1.3
1
1
3
-3
3
March
6.9
9
6
9
8
5
April
12.5
13
11
14
12
May
20.1
24
16
18
19
June
22.8
25
22
25
20
July
25.3
27
26
28
23
August
25.3
26
28
25
23
September
19.3
21
23
19
19
October
11.7
14
16
11
8
November
3.4
5
-2
6
4
December
-2.1
4
-10
-9
2
Average
10.9
2.1
13.8
12.3
12.1
11.2
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
-9.4
-10
-7
-9
-6
-11
February
-11.6
-9
-7
-7
-13
-6
March
-6.7
-6
-9
-2
-2
-7
April
-2.8
0
-3
-1
-3
May
4.9
7
3
4
5
June
7.7
9
8
10
8
July
9.1
10
10
11
10
August
9.9
10
12
10
9
September
6.3
5
6
7
9
October
0.8
0
2
1
1
November
-4.7
-2
-8
-1
-3
December
-9.4
-2
-18
-18
-4
Average
-1.2
-9.9
1.3
0.1
0.1
0.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
18.2
28
20
22
21
17
February
24.3
27
40
29
16
8
March
12.8
5
24
15
6
12
April
7.4
5
10
9
6
May
7.5
6
17
6
9
June
8.7
9
13
8
13
July
7.5
7
10
3
16
August
7.2
13
8
6
9
September
9.2
10
7
10
11
October
10.6
5
7
11
24
November
20.2
19
42
11
15
December
19.4
20
39
26
6
Average
12.5
20.1
14.4
17.0
9.9
12.0
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
4.8
4
4
5
6
5
February
5.5
4
6
6
5
6
March
5.2
6
4
6
6
6
April
5.7
7
6
6
5
May
4.2
4
5
4
5
June
4.3
5
5
4
4
July
3.5
3
4
4
3
August
3.7
4
3
4
4
September
4.0
3
3
5
4
October
5.2
5
4
5
5
November
5.7
4
7
6
6
December
4.7
5
4
4
5
Average
4.7
4.6
4.5
4.7
4.9
4.7
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
207°
149°
155°
157°
149°
February
265°
141°
140°
129°
142°
March
212°
323°
162°
152°
314°
April
161°
294°
300°
319°
May
329°
252°
302°
328°
June
337°
182°
236°
013°
July
318°
331°
333°
180°
August
270°
203°
327°
151°
September
164°
194°
161°
154°
October
170°
174°
153°
321°
November
153°
313°
151°
148°
December
152°
321°
173°
152°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.