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
92.3
90
91
94
99
February
87.4
82
88
91
93
March
87.0
83
81
92
90
April
91.9
93
91
92
91
May
96.4
97
98
95
June
92.9
96
79
98
July
90.8
100
73
100
August
98.6
97
100
100
September
93.0
89
98
99
October
90.5
88
91
95
November
89.7
95
88
98
December
92.1
100
85
88
Average
91.6
86.8
92.8
90.4
93.7
96.0
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
1.7
0
2
3
2
February
-1.8
1
2
2
5
March
3.8
5
0
9
7
April
10.8
13
11
10
10
May
17.3
20
16
17
June
21.5
22
22
22
July
26.9
29
28
26
August
28.6
28
31
29
September
22.6
23
25
24
October
11.7
12
15
12
November
5.1
9
-1
10
December
1.6
8
-7
-1
Average
9.3
4.5
13.7
13.0
6.3
14.9
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
-10.6
-13
-7
-10
-9
February
-11.2
-8
-8
-11
-7
March
-8.8
-7
-8
-5
-5
April
-2.1
-1
-1
-4
-3
May
4.4
7
2
4
June
9.2
10
7
9
July
10.7
10
10
11
August
11.4
12
13
11
September
7.0
7
8
7
October
-1.4
-1
3
0
November
-6.0
-3
-11
-3
December
-10.7
-5
-16
-14
Average
-3.0
-8.7
0.9
-1.1
-7.6
1.4
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.0
13
0
13
4
February
19.2
20
13
17
11
March
13.8
13
20
15
8
April
12.7
7
16
16
12
May
6.2
9
4
7
June
7.2
4
8
11
July
1.7
0
2
4
August
2.0
4
1
2
September
6.9
7
6
1
October
9.9
11
9
6
November
8.1
5
1
3
December
9.4
2
3
22
Average
10.1
13.2
7.7
7.8
9.9
6.9
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
11.0
10
10
13
11
February
11.5
9
14
13
13
March
9.2
8
8
10
14
April
10.6
10
11
12
10
May
8.6
7
11
9
June
8.2
6
9
10
July
7.0
6
7
9
August
7.1
8
7
7
September
8.5
8
8
8
October
9.7
8
10
12
November
11.2
11
12
15
December
10.9
11
9
11
Average
10.1
9.2
8.7
9.9
12.5
9.8
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
229°
226°
226°
225°
February
234°
233°
248°
246°
March
257°
288°
260°
251°
April
269°
240°
265°
269°
May
259°
251°
236°
June
234°
269°
265°
July
237°
269°
242°
August
241°
271°
243°
September
239°
280°
268°
October
243°
236°
232°
November
221°
251°
225°
December
212°
273°
245°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.