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
77.8
53
83
97
75
74
February
90.5
90
93
98
84
96
March
83.4
90
87
96
85
67
April
91.8
99
97
94
91
May
88.0
89
88
90
89
June
97.6
99
98
98
99
July
95.2
95
93
93
95
August
92.7
93
93
97
97
September
92.0
91
96
91
94
October
89.4
90
99
86
94
November
93.1
96
98
96
93
December
87.4
86
80
96
85
Average
88.9
78.6
91.9
94.6
90.7
89.6
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
1.7
-3
1
6
3
2
February
4.4
11
5
7
-4
7
March
11.5
13
9
14
14
13
April
17.7
19
18
19
18
May
23.1
26
23
22
22
June
29.9
29
29
31
32
July
29.6
29
31
30
30
August
28.4
29
30
30
30
September
26.8
28
28
28
25
October
18.0
18
21
20
17
November
11.4
13
10
14
14
December
5.1
6
3
9
6
Average
16.0
6.7
17.6
18.8
18.0
17.9
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
-8.5
-10
-7
-9
-4
-5
February
-8.3
-3
-7
-9
-14
-5
March
-2.8
-1
-4
-3
2
2
April
2.9
2
3
4
2
May
10.8
11
11
11
11
June
16.9
15
16
18
19
July
18.5
17
19
18
20
August
16.8
17
18
19
18
September
13.4
13
13
14
12
October
4.7
6
4
7
4
November
-2.6
-1
-4
1
1
December
-6.6
-4
-8
-4
-5
Average
3.9
-5.1
4.9
4.7
6.0
6.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
5.1
7
7
3
9
6
February
4.9
2
6
1
9
3
March
5.8
3
3
5
12
4
April
4.9
2
3
7
6
May
4.6
1
6
4
7
June
2.1
3
1
1
1
July
2.4
3
3
2
2
August
2.2
1
1
0
1
September
2.3
2
3
2
3
October
4.6
4
2
4
1
November
4.3
7
3
4
4
December
5.8
8
5
1
9
Average
4.0
3.9
3.6
2.9
4.4
3.7
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
9.8
10
9
11
10
10
February
10.5
11
11
13
7
11
March
12.1
13
12
14
12
11
April
13.2
15
17
13
12
May
10.4
9
12
11
11
June
9.4
7
10
8
12
July
6.8
6
8
7
7
August
6.7
6
6
8
8
September
8.2
7
8
8
8
October
10.2
11
10
10
10
November
10.6
11
12
10
10
December
9.9
9
13
11
8
Average
9.9
11.3
9.3
10.9
9.4
9.7
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
315°
341°
293°
326°
310°
February
292°
296°
327°
344°
317°
March
359°
341°
348°
099°
265°
April
297°
284°
312°
319°
May
137°
219°
142°
033°
June
146°
188°
173°
172°
July
101°
152°
159°
140°
August
190°
149°
154°
166°
September
176°
159°
173°
282°
October
319°
265°
316°
332°
November
261°
289°
282°
250°
December
306°
291°
301°
317°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.