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
83.4
70
69
79
94
94
February
84.3
88
86
80
79
85
March
83.4
72
76
79
87
93
April
86.2
88
76
88
92
94
May
91.6
89
89
97
96
June
89.3
77
89
98
93
July
90.5
75
96
90
92
August
90.2
79
92
89
95
September
87.2
79
79
91
92
October
81.6
78
72
86
82
November
88.3
89
85
96
89
December
80.8
68
76
76
86
Average
86.4
79.8
78.3
84.4
90.1
91.1
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
0.1
0
2
-3
0
2
February
2.0
4
2
2
0
2
March
5.8
7
6
7
8
8
April
12.5
13
13
12
14
11
May
20.3
21
22
21
20
June
24.8
23
24
28
26
July
27.8
28
30
25
29
August
26.6
25
28
28
27
September
22.7
23
21
23
24
October
15.8
17
17
17
14
November
7.7
7
11
9
11
December
2.0
4
4
3
3
Average
13.1
6.4
14.4
15.1
14.5
14.6
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
-11.1
-8
-6
-17
-10
-10
February
-11.9
-8
-11
-11
-12
-10
March
-6.5
-2
-4
-5
-6
-4
April
0.5
1
2
1
1
0
May
6.2
5
7
7
6
June
11.8
12
11
14
12
July
15.2
17
14
15
17
August
14.1
14
15
16
14
September
9.9
11
9
11
8
October
4.5
6
3
6
3
November
-4.9
-4
-1
-3
-1
December
-8.2
-5
-5
-7
-6
Average
1.3
-5.6
3.2
2.0
2.5
2.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
15.4
29
27
17
9
7
February
14.2
6
13
21
19
13
March
12.2
19
19
16
5
8
April
13.5
13
15
16
10
15
May
7.5
10
7
5
4
June
8.3
20
6
1
3
July
7.1
17
6
12
2
August
5.6
12
7
3
3
September
6.7
8
15
5
1
October
11.5
15
9
10
8
November
11.4
10
17
7
6
December
13.2
17
22
14
10
Average
10.6
15.9
15.1
12.1
7.7
6.1
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
3.5
3
3
3
3
3
February
4.2
4
4
4
3
4
March
5.0
5
5
5
5
5
April
5.1
5
5
5
5
6
May
5.0
5
4
5
6
June
4.1
4
4
5
4
July
3.6
3
4
4
4
August
3.4
3
3
3
4
September
3.3
2
3
4
5
October
3.3
3
3
3
4
November
3.8
3
4
3
4
December
3.5
3
5
3
4
Average
4.1
4.2
3.5
3.9
3.9
4.3
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
339°
343°
336°
344°
277°
February
316°
303°
276°
313°
283°
March
319°
345°
292°
287°
329°
April
031°
068°
314°
333°
328°
May
319°
116°
282°
287°
June
072°
232°
225°
015°
July
145°
244°
327°
155°
August
294°
163°
155°
287°
September
023°
329°
257°
202°
October
105°
156°
347°
266°
November
292°
271°
284°
265°
December
192°
335°
292°
280°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.