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
72.5
95
94
16
96
February
92.2
94
92
94
86
March
92.9
95
90
93
98
67
April
95.8
97
95
96
95
May
98.2
98
98
98
99
June
97.5
96
100
100
98
July
89.1
100
100
13
100
August
96.5
100
99
86
100
September
99.2
99
100
99
October
96.2
99
97
90
November
96.9
100
95
92
99
December
79.7
99
97
0
96
Average
92.0
94.6
95.9
91.1
81.0
97.3
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
2.9
1
4
1
5
February
3.0
7
4
4
-4
March
8.3
10
4
11
9
7
April
11.8
15
11
8
14
May
19.7
23
19
18
20
June
25.7
24
25
31
26
July
25.0
30
33
6
30
August
29.7
35
33
25
32
September
27.4
29
27
26
October
16.2
18
17
13
November
8.7
11
3
12
10
December
3.9
8
-1
0
7
Average
13.5
6.0
13.8
15.7
12.1
19.8
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
-5.1
-11
-6
0
-3
February
-9.9
-4
-7
-9
-13
March
-4.8
-3
-6
-2
-1
0
April
-1.8
1
-2
0
1
May
6.6
8
6
6
7
June
12.4
12
11
17
11
July
11.6
14
15
3
14
August
13.7
23
16
11
14
September
10.1
11
10
9
October
3.1
4
5
0
November
-3.5
-2
-7
1
-2
December
-4.0
-3
-12
0
-3
Average
1.3
-6.0
1.4
2.9
2.4
5.7
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
0.0
0
0
0
0
February
0.0
0
0
0
0
March
0.0
0
0
0
0
0
April
0.0
0
0
0
0
May
0.0
0
0
0
0
June
0.0
0
0
0
0
July
0.0
0
0
0
0
August
0.0
0
0
0
0
September
0.0
0
0
0
October
0.0
0
0
0
November
0.0
0
0
0
0
December
0.0
0
0
0
0
Average
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
8.1
10
10
2
12
February
11.2
10
12
13
10
March
8.7
8
8
10
9
7
April
10.5
11
12
9
9
May
8.0
7
9
8
8
June
7.1
6
8
8
8
July
6.1
7
7
1
6
August
7.7
8
9
7
7
September
8.3
8
8
9
October
9.4
9
10
10
November
10.7
10
11
11
12
December
8.5
11
8
0
11
Average
8.7
9.4
8.8
8.8
7.6
8.7
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
233°
237°
241°
248°
February
243°
240°
246°
264°
March
263°
344°
261°
234°
157°
April
260°
306°
291°
285°
May
029°
297°
005°
345°
June
004°
267°
320°
284°
July
239°
252°
215°
355°
August
287°
215°
276°
133°
September
247°
219°
252°
October
251°
234°
266°
November
237°
253°
246°
242°
December
241°
256°
360°
242°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.