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
73.8
63
65
89
75
88
February
88.3
91
98
72
96
96
March
89.7
86
87
89
95
94
April
85.1
84
82
85
95
May
94.4
93
92
98
97
June
95.8
95
96
99
99
July
97.7
98
98
98
100
August
93.6
91
96
91
94
September
92.6
92
95
97
96
October
89.7
90
94
83
91
November
86.1
89
82
86
91
December
72.6
68
76
74
73
Average
89.1
81.5
87.9
89.9
90.2
93.8
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
-8.1
-4
-6
-11
-5
-5
February
-6.2
2
-2
-10
-10
-4
March
2.0
3
1
0
6
4
April
7.6
8
5
10
7
May
17.8
21
18
18
17
June
23.0
25
25
24
24
July
24.2
23
24
27
23
August
23.7
24
24
25
24
September
18.6
22
19
19
17
October
9.7
12
13
13
6
November
1.0
3
2
0
4
December
-4.4
2
-5
-5
-4
Average
8.7
0.3
11.9
9.0
10.1
10.3
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
-18.3
-11
-14
-26
-14
-12
February
-19.6
-10
-14
-24
-20
-21
March
-11.2
-9
-15
-12
-7
-10
April
-5.7
-6
-5
-2
-5
May
3.4
4
4
3
2
June
9.7
10
10
12
10
July
11.5
9
11
12
14
August
11.2
10
12
13
11
September
7.6
9
7
9
5
October
1.2
3
0
5
-3
November
-7.2
-6
-7
-6
-6
December
-12.5
-5
-13
-13
-11
Average
-3.7
-10.4
0.1
-4.6
-1.2
-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
16.2
26
13
16
9
8
February
18.7
15
8
40
11
9
March
11.8
15
12
14
7
11
April
18.1
19
25
17
6
May
5.1
0
11
3
2
June
4.7
0
6
6
4
July
3.2
0
7
1
4
August
2.7
0
5
5
4
September
5.0
0
8
8
5
October
7.5
3
5
6
15
November
20.4
13
28
21
17
December
22.3
16
28
35
17
Average
11.1
17.7
6.0
14.0
9.7
7.9
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
2.7
2
2
4
2
1
February
4.0
4
4
5
5
4
March
4.2
4
4
4
4
4
April
3.8
4
3
4
4
May
3.7
4
4
4
4
June
3.1
2
4
3
4
July
2.9
3
3
3
3
August
2.6
2
3
4
3
September
2.8
2
3
3
4
October
3.4
3
4
3
3
November
3.4
4
3
4
3
December
2.6
3
3
3
3
Average
3.3
3.7
3.0
3.4
3.4
3.7
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
262°
298°
269°
254°
180°
February
290°
263°
302°
263°
254°
March
323°
321°
311°
245°
255°
April
339°
333°
339°
320°
May
055°
232°
271°
322°
June
146°
251°
270°
229°
July
296°
284°
279°
282°
August
290°
257°
234°
241°
September
179°
262°
232°
248°
October
312°
239°
223°
251°
November
265°
271°
285°
240°
December
243°
291°
238°
243°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.