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
84.7
77
85
87
86
85
February
89.0
96
90
84
86
84
March
91.6
85
91
93
99
99
April
93.1
93
96
96
87
95
May
96.8
98
97
100
98
June
90.3
89
95
67
96
July
94.3
89
98
89
95
August
96.8
95
97
98
99
September
92.7
89
90
98
96
October
91.4
92
99
91
92
November
92.4
96
98
95
99
December
87.7
80
87
90
89
Average
91.8
88.1
91.1
93.8
90.3
94.6
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
-2.8
-1
1
-4
-2
0
February
1.2
3
2
1
-2
0
March
5.0
7
4
6
7
8
April
12.3
13
15
12
13
10
May
19.5
19
22
20
19
June
23.8
23
24
26
25
July
26.6
27
27
24
29
August
25.4
23
27
27
27
September
21.2
22
20
21
20
October
15.0
13
16
17
14
November
6.5
6
10
7
11
December
1.6
4
3
4
2
Average
11.8
5.3
13.3
13.8
13.2
12.7
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
-9.2
-7
-4
-15
-8
-7
February
-8.3
-6
-9
-10
-9
-7
March
-5.8
-2
-4
-4
-4
-2
April
2.0
2
4
2
2
1
May
7.7
6
9
8
7
June
12.9
13
13
15
14
July
16.1
17
15
15
17
August
15.2
14
15
16
17
September
11.5
12
11
12
8
October
6.0
7
5
9
5
November
-2.9
-1
2
-2
1
December
-6.3
-2
-4
-4
-5
Average
2.5
-4.9
4.2
3.3
3.9
3.1
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
20
15
12
14
20
February
13.3
4
15
17
18
17
March
14.2
18
18
15
4
11
April
16.1
19
11
17
19
17
May
9.6
8
7
7
6
June
9.3
13
8
5
6
July
9.2
14
6
19
4
August
6.7
11
4
10
12
September
7.7
9
13
6
4
October
13.5
24
4
13
16
November
12.4
7
9
10
8
December
18.2
23
24
12
17
Average
12.2
15.5
13.3
10.6
11.2
10.4
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
5.1
5
5
6
5
5
February
5.8
6
6
7
4
6
March
5.8
5
6
6
5
7
April
5.9
6
6
6
5
6
May
4.9
5
5
4
6
June
4.4
4
5
4
4
July
3.8
3
4
3
4
August
3.8
4
4
3
3
September
3.8
3
4
5
5
October
4.6
4
4
4
5
November
5.1
5
6
3
7
December
4.4
4
5
4
5
Average
4.9
5.5
4.5
5.0
4.1
5.3
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
183°
331°
330°
350°
199°
February
281°
210°
207°
292°
224°
March
321°
325°
205°
277°
209°
April
209°
176°
327°
343°
315°
May
324°
241°
301°
287°
June
340°
244°
189°
194°
July
192°
199°
306°
194°
August
180°
200°
178°
200°
September
317°
308°
196°
232°
October
191°
195°
177°
192°
November
207°
194°
203°
201°
December
214°
328°
217°
201°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.