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
78.6
57
86
95
82
72
February
90.8
92
94
100
84
94
March
86.5
95
87
96
84
74
April
93.8
94
100
97
96
93
May
91.1
95
89
92
89
June
97.8
99
100
96
99
July
97.1
98
93
97
96
August
95.4
91
99
99
100
September
92.8
95
96
97
89
October
91.0
95
100
92
90
November
94.2
95
100
96
95
December
90.0
86
77
95
92
Average
91.1
85.2
93.4
95.5
92.8
90.4
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
2.6
-2
3
5
4
3
February
6.1
13
8
8
-3
7
March
12.7
14
11
13
15
14
April
18.9
21
21
19
18
19
May
24.0
26
24
22
22
June
30.4
31
30
31
31
July
31.0
30
31
31
30
August
30.3
31
32
32
30
September
28.1
29
29
29
26
October
18.9
20
21
21
17
November
11.9
14
11
14
15
December
6.7
7
5
11
7
Average
17.6
11.5
19.2
19.5
18.8
18.3
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
-8.9
-10
-6
-10
-4
-6
February
-7.6
-2
-6
-9
-12
-5
March
0.3
1
-2
-2
3
3
April
4.7
5
5
5
5
4
May
12.3
13
13
12
11
June
17.8
16
18
18
19
July
19.8
19
20
19
20
August
18.5
19
18
20
18
September
14.9
14
14
15
12
October
6.2
8
5
8
4
November
-1.2
0
-2
1
1
December
-5.5
-2
-5
-3
-6
Average
5.4
-2.5
6.5
5.8
6.7
6.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
5.7
8
6
4
10
5
February
4.6
2
1
1
10
3
March
4.9
2
4
5
10
5
April
4.4
3
1
3
5
5
May
4.3
4
8
3
6
June
1.8
2
1
0
1
July
2.5
3
4
2
2
August
2.6
4
2
1
0
September
2.8
2
3
1
6
October
4.7
2
3
5
0
November
3.6
9
0
3
4
December
5.2
10
4
0
4
Average
3.9
3.7
3.7
3.3
3.8
3.3
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
8
9
9
9
February
9.6
9
9
11
8
10
March
11.1
11
11
12
12
10
April
11.8
12
13
14
11
11
May
9.0
8
10
9
10
June
7.9
6
4
7
11
July
6.6
6
7
6
7
August
6.6
6
6
8
7
September
8.1
8
7
8
9
October
9.2
10
8
9
9
November
9.6
9
12
9
11
December
8.7
8
10
9
8
Average
9.0
10.1
8.4
9.0
8.7
9.1
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
318°
330°
292°
323°
305°
February
273°
282°
319°
360°
316°
March
002°
335°
348°
162°
222°
April
280°
270°
252°
283°
316°
May
159°
168°
144°
023°
June
148°
210°
167°
176°
July
108°
167°
157°
142°
August
120°
168°
164°
166°
September
180°
169°
190°
234°
October
308°
254°
314°
324°
November
228°
279°
261°
231°
December
293°
250°
246°
310°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.