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
77.3
71
65
91
72
83
February
86.5
88
83
92
88
96
March
86.8
94
77
76
96
83
April
87.7
85
89
84
94
92
May
91.6
94
92
94
90
June
92.8
80
90
93
98
July
95.8
97
94
92
97
August
94.3
95
90
94
98
September
93.1
94
90
97
95
October
92.4
91
95
88
97
November
90.9
92
85
93
90
December
84.5
81
88
83
96
Average
89.5
85.0
86.9
88.8
90.9
93.0
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
-3.8
-2
-1
-5
-2
0
February
0.0
6
1
-1
-5
-1
March
5.2
9
3
4
9
5
April
12.0
15
14
10
14
11
May
20.1
21
22
20
19
June
25.9
26
27
28
26
July
27.8
28
28
27
29
August
26.1
26
27
27
27
September
22.8
24
23
23
21
October
14.8
16
17
18
12
November
6.4
8
9
7
11
December
1.2
5
1
2
1
Average
12.5
6.8
14.2
13.8
14.1
13.4
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
-9.6
-6
-5
-14
-7
-6
February
-9.1
-4
-7
-10
-13
-10
March
-4.8
-1
-5
-3
-1
-1
April
2.3
4
3
2
3
2
May
8.8
8
11
8
8
June
14.6
14
15
16
14
July
16.9
16
17
16
19
August
15.5
15
17
17
16
September
12.2
13
13
11
11
October
5.8
7
5
9
3
November
-2.7
-1
-1
-1
1
December
-6.7
-1
-5
-5
-5
Average
3.3
-2.1
4.7
4.2
4.5
4.2
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
12.7
17
18
12
5
7
February
10.0
3
18
10
8
5
March
10.2
9
14
18
5
14
April
10.8
19
11
16
4
6
May
7.1
7
6
6
9
June
6.9
8
6
5
8
July
3.4
3
5
5
3
August
4.1
4
6
3
3
September
5.5
4
9
3
8
October
8.8
15
6
5
8
November
10.1
7
21
8
7
December
8.8
9
8
9
3
Average
8.4
12.3
9.4
10.1
5.3
6.8
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
8.4
8
8
9
8
8
February
9.3
8
10
10
8
9
March
9.6
11
9
10
10
9
April
10.0
11
10
10
9
11
May
8.8
8
9
8
10
June
7.7
7
8
8
7
July
6.1
5
7
6
6
August
6.2
7
7
6
6
September
7.1
6
7
7
8
October
8.7
9
7
8
9
November
9.0
8
10
9
10
December
8.2
8
8
8
8
Average
8.4
9.7
7.8
8.4
7.9
8.3
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
300°
296°
270°
305°
285°
February
251°
274°
294°
262°
270°
March
299°
008°
324°
235°
241°
April
330°
260°
212°
284°
331°
May
034°
127°
206°
014°
June
026°
253°
242°
192°
July
272°
275°
341°
269°
August
359°
281°
200°
227°
September
118°
321°
279°
246°
October
301°
238°
012°
276°
November
251°
240°
255°
243°
December
280°
190°
256°
271°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.