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
79.4
76
77
84
83
81
February
83.5
92
88
86
81
83
March
88.4
90
87
87
94
89
April
90.8
95
91
94
95
May
93.3
96
93
99
94
June
93.2
87
94
96
97
July
93.8
88
94
94
96
August
95.4
94
93
97
95
September
93.5
88
92
98
93
October
89.5
89
97
83
90
November
90.6
93
87
91
95
December
78.9
63
80
85
83
Average
89.6
86.5
87.9
90.6
92.1
91.5
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
-2.0
-1
0
-5
-2
-1
February
0.7
4
2
0
-2
0
March
5.0
8
4
5
7
7
April
12.3
15
13
14
10
May
19.6
20
22
20
19
June
24.3
24
24
26
25
July
27.5
28
27
25
29
August
26.2
25
27
28
26
September
22.1
23
21
22
21
October
15.8
17
17
17
14
November
6.7
6
9
7
10
December
1.0
3
2
3
2
Average
12.2
3.5
13.8
13.7
13.7
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
-11.0
-7
-7
-20
-10
-9
February
-11.8
-7
-11
-13
-13
-11
March
-5.3
-1
-4
-6
-5
-2
April
2.1
3
3
3
1
May
7.9
6
9
8
7
June
13.1
13
13
15
13
July
16.0
17
16
15
17
August
15.0
14
16
17
15
September
10.7
11
11
11
9
October
5.5
8
4
8
4
November
-2.2
-2
0
-2
1
December
-7.4
-3
-5
-5
-5
Average
2.0
-6.7
3.8
2.6
3.4
3.3
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
18.4
19
24
14
12
15
February
16.0
8
17
17
19
18
March
11.5
10
17
11
6
9
April
9.9
7
7
8
7
May
6.5
5
5
1
4
June
4.9
2
5
3
1
July
3.5
3
2
5
2
August
2.9
2
3
2
5
September
3.2
1
3
4
2
October
9.0
9
3
8
8
November
10.2
5
11
6
5
December
17.0
22
15
8
11
Average
9.1
12.1
8.5
7.1
6.1
6.6
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
6.1
6
5
6
5
6
February
6.8
6
7
8
6
7
March
7.0
7
7
7
8
7
April
7.3
7
8
7
8
May
6.0
5
6
6
7
June
5.4
4
5
7
5
July
4.8
4
6
4
5
August
4.3
4
4
4
4
September
4.5
4
4
5
5
October
5.8
5
5
5
7
November
6.7
6
7
6
8
December
5.9
5
7
6
7
Average
5.9
6.3
5.2
5.9
5.8
6.3
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
237°
299°
274°
299°
261°
February
234°
233°
232°
242°
238°
March
259°
274°
252°
246°
235°
April
226°
278°
285°
261°
May
262°
244°
249°
257°
June
337°
234°
218°
227°
July
223°
225°
272°
224°
August
233°
224°
222°
245°
September
229°
264°
228°
216°
October
228°
213°
258°
225°
November
233°
225°
238°
228°
December
257°
213°
224°
237°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.