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
72.6
59
57
91
77
71
February
84.9
91
87
90
76
93
March
84.8
95
82
86
87
70
April
91.1
92
90
96
90
May
89.7
91
91
87
90
June
95.1
89
95
99
96
July
94.8
82
96
96
98
August
94.2
93
91
98
98
September
93.2
93
95
97
88
October
92.2
89
99
94
94
November
88.4
98
84
97
82
December
84.3
78
67
90
86
Average
88.3
81.3
85.9
90.6
91.8
88.1
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
-3
-1
-3
-2
-2
February
1.3
10
4
0
-10
1
March
8.5
12
7
9
12
10
April
14.9
17
13
16
15
May
22.0
25
23
20
20
June
28.1
28
28
30
28
July
28.6
26
29
29
30
August
27.6
29
28
29
28
September
25.2
27
25
27
23
October
16.1
18
18
18
14
November
8.2
11
9
10
12
December
3.4
6
2
6
2
Average
14.0
6.6
16.5
15.4
15.8
14.6
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
-11.9
-9
-8
-15
-9
-9
February
-10.7
-3
-7
-12
-18
-8
March
-2.4
-1
-3
-2
1
1
April
2.7
4
1
4
2
May
10.3
11
11
9
9
June
16.5
16
16
17
17
July
17.5
14
18
18
19
August
16.2
17
17
17
17
September
13.0
14
12
13
11
October
5.2
7
3
8
3
November
-3.8
-1
-2
-1
0
December
-6.0
-2
-6
-5
-8
Average
3.3
-5.6
5.2
3.9
4.9
4.0
Average lowest temperature per day
The minimum temperature is typically observed just before sunrise.
Precipitation (%)
Month
Average
2024
2023
2022
2021
2020
January
9.9
16
13
7
5
13
February
8.8
0
13
11
14
5
March
9.4
9
13
14
8
9
April
7.2
5
9
2
7
May
6.3
2
6
8
7
June
4.0
5
7
3
5
July
2.1
5
2
2
2
August
3.4
4
4
2
1
September
5.4
4
5
1
11
October
7.5
6
5
11
2
November
5.7
0
17
2
4
December
8.4
11
21
2
7
Average
6.6
8.7
6.6
8.1
4.5
6.0
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
10.6
10
10
11
10
11
February
11.2
12
12
13
9
11
March
12.0
13
12
12
13
11
April
12.8
14
15
12
12
May
10.3
10
12
10
10
June
9.1
8
10
8
10
July
7.1
6
8
7
7
August
7.3
7
7
8
8
September
8.7
8
9
8
10
October
10.7
11
10
10
12
November
11.2
10
12
12
12
December
10.5
10
12
11
10
Average
10.2
11.5
9.7
10.7
9.8
10.2
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
302°
294°
289°
344°
291°
February
269°
294°
306°
337°
320°
March
359°
335°
328°
131°
283°
April
266°
245°
270°
292°
May
123°
149°
142°
045°
June
123°
209°
213°
163°
July
301°
229°
178°
164°
August
185°
171°
157°
193°
September
173°
232°
197°
217°
October
300°
254°
019°
285°
November
239°
264°
262°
228°
December
245°
194°
224°
284°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.