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
83.7
72
85
96
82
February
92.9
89
93
100
91
March
93.3
95
91
97
90
April
97.8
96
100
98
97
May
92.5
93
95
90
June
98.4
98
99
98
July
94.1
95
91
96
August
96.1
97
96
96
95
September
96.6
96
99
96
97
October
96.0
95
100
95
95
November
95.3
88
98
97
97
December
91.6
81
87
98
91
Average
93.6
88.7
93.9
96.4
93.9
94.9
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
4.2
2
3
7
6
February
7.0
13
7
9
0
March
13.6
15
10
14
15
April
19.9
20
21
21
19
May
23.8
25
25
22
June
30.6
29
32
30
July
32.5
32
33
33
August
33.2
33
33
34
33
September
29.7
30
30
32
27
October
20.2
19
23
21
18
November
15.1
17
12
16
16
December
8.8
6
7
12
9
Average
18.6
11.9
20.2
20.8
20.0
20.2
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
-7.3
-8
-6
-8
-4
February
-7.4
-1
-7
-8
-11
March
-2.7
-1
-3
-3
1
April
3.7
5
3
4
3
May
10.3
11
10
10
June
16.1
15
17
16
July
18.3
18
19
19
August
17.3
17
16
18
18
September
12.3
14
12
14
10
October
4.8
6
4
6
3
November
-1.4
2
-4
1
0
December
-5.3
-2
-7
-4
-5
Average
4.1
-2.7
6.3
4.7
5.7
5.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
5.2
4
7
6
5
February
5.5
3
8
1
11
March
6.0
6
4
4
11
April
1.4
1
2
1
2
May
6.1
6
8
4
June
1.6
3
2
1
July
1.6
2
1
2
August
1.1
3
1
1
0
September
3.5
2
4
2
6
October
1.5
3
2
0
2
November
1.8
3
2
1
1
December
3.1
14
1
1
3
Average
3.1
3.4
3.9
2.7
3.2
2.5
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
8.7
8
7
10
10
February
9.1
9
9
11
7
March
10.5
10
10
11
11
April
12.8
13
13
15
11
May
8.9
8
10
9
June
8.4
7
10
8
July
7.8
7
9
8
August
8.1
8
7
9
8
September
8.3
8
7
9
9
October
9.3
10
8
10
9
November
9.6
8
10
9
11
December
9.6
10
11
8
10
Average
9.4
10.3
8.6
9.8
9.1
9.2
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
338°
343°
313°
341°
February
320°
310°
346°
019°
March
032°
356°
359°
019°
April
347°
313°
316°
340°
May
139°
080°
150°
June
137°
178°
166°
July
115°
147°
163°
August
240°
137°
158°
177°
September
183°
157°
157°
087°
October
337°
294°
346°
006°
November
252°
310°
314°
269°
December
333°
303°
324°
331°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.