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
January
80.6
77
85
100
February
87.9
80
95
97
March
94.7
92
97
97
April
97.9
100
96
May
98.0
98
99
June
98.0
98
98
July
99.7
100
100
August
98.0
99
97
September
97.7
97
99
October
92.3
91
90
96
November
89.2
82
93
96
December
80.7
79
85
80
Average
91.9
83.3
91.3
95.9
97.1
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
January
-2.7
-1
1
-6
February
4.0
5
4
3
March
10.2
11
8
12
April
13.3
16
11
May
20.9
25
17
June
23.8
25
22
July
33.3
33
34
August
31.7
34
30
September
25.8
27
25
October
16.4
15
18
16
November
4.8
5
1
8
December
-1.9
3
-2
-2
Average
12.2
4.9
11.0
15.8
17.1
Average highest temperature per day
The maximum temperature is typically observed some hours after noon.
Minimum temperatures (°C)
Month
Average
2024
2023
2022
2021
January
-8.8
-8
-6
-7
February
-5.1
-3
-6
-6
March
-2.0
-2
-4
-1
April
-2.5
0
-3
May
6.3
8
4
June
10.4
10
11
July
11.1
11
12
August
11.3
12
11
September
6.3
7
6
October
2.1
2
3
2
November
-3.3
-2
-6
0
December
-5.4
-3
-9
-3
Average
0.3
-5.8
-1.6
2.0
3.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
January
9.8
16
0
0
February
11.5
23
0
0
March
4.3
10
0
0
April
0.0
0
0
May
0.0
0
0
June
0.0
0
0
July
0.0
0
0
August
0.0
0
0
September
0.0
0
0
October
3.2
8
0
0
November
6.3
15
0
0
December
5.6
8
0
0
Average
5.1
16.3
4.0
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
January
1.2
2
0
0
February
1.7
3
1
1
March
2.0
3
1
2
April
2.1
2
3
May
1.3
1
2
June
0.8
1
1
July
0.8
1
1
August
1.1
1
1
September
1.0
1
2
October
1.1
2
0
1
November
1.0
2
1
1
December
1.0
1
0
1
Average
1.4
2.5
1.2
1.0
1.0
Average wind speed
Excluding wind gusts. Only observations between sunrise and sunset are taken into account.
Prevailing wind direction
Month
2024
2023
2022
2021
January
177°
270°
360°
February
231°
239°
108°
March
249°
182°
238°
April
238°
270°
May
299°
236°
June
233°
236°
July
249°
261°
August
235°
245°
September
251°
255°
October
236°
227°
242°
November
234°
171°
205°
December
190°
109°
270°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.