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
89.3
92
84
86
96
February
90.7
90
91
91
90
March
86.2
90
88
91
80
April
93.1
93
94
May
87.0
91
0
78
91
June
95.8
93
100
100
100
July
92.9
91
95
94
August
97.8
100
98
100
September
95.9
96
95
99
October
94.4
94
100
97
November
91.2
97
93
94
December
93.2
95
89
99
Average
91.8
90.7
92.6
94.5
93.0
90.5
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
2.3
2
-1
2
6
February
4.2
7
2
4
4
March
8.7
11
6
7
10
April
14.4
15
14
May
18.6
20
0
17
19
June
25.8
23
30
28
28
July
29.4
29
31
28
August
28.8
29
30
26
September
26.0
26
27
25
October
15.9
17
17
17
November
9.9
11
7
14
December
6.1
8
3
8
Average
14.0
6.6
15.4
16.6
16.2
13.7
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
-8.3
-10
-8
-7
-6
February
-7.0
-4
-8
-8
-8
March
-4.2
-3
-5
-6
-2
April
-2.7
-1
-2
May
6.2
8
0
6
6
June
12.8
12
14
16
11
July
15.2
14
16
15
August
14.4
14
14
20
September
9.9
10
10
9
October
1.5
2
3
3
November
-4.9
-2
-6
0
December
-6.7
-4
-8
-6
Average
1.0
-6.3
2.7
3.0
2.4
0.8
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
12.0
8
16
19
8
February
13.2
12
12
10
21
March
9.9
11
9
11
10
April
10.3
9
12
May
6.3
5
0
12
3
June
3.8
6
1
0
2
July
3.1
3
2
6
August
0.9
2
0
0
September
1.2
1
2
0
October
5.0
5
2
4
November
7.9
5
6
3
December
5.9
4
11
2
Average
7.0
10.1
6.0
4.8
4.4
9.0
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
2020
January
12.2
11
10
13
15
February
13.1
11
13
14
14
March
12.3
11
13
11
13
April
11.9
12
12
May
10.7
10
0
10
12
June
9.1
9
10
9
11
July
9.1
9
9
9
August
9.3
9
9
9
September
9.9
10
9
10
October
11.5
10
10
12
November
12.7
12
12
13
December
13.8
14
15
14
Average
11.5
11.1
10.8
10.8
12.0
12.4
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
307°
123°
319°
307°
February
285°
115°
308°
323°
March
280°
120°
299°
300°
April
137°
320°
May
164°
360°
155°
173°
June
146°
203°
175°
306°
July
312°
299°
028°
August
282°
006°
144°
September
321°
120°
309°
October
319°
137°
319°
November
305°
129°
305°
December
305°
119°
278°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.