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
92.9
92
91
95
95
February
90.7
87
91
94
92
March
85.7
92
82
93
77
April
93.3
94
95
99
93
May
90.4
88
94
88
June
96.2
94
98
99
July
94.5
93
96
93
August
96.5
98
97
100
September
95.8
96
96
October
96.0
93
100
November
94.8
96
96
100
December
93.9
96
87
96
Average
92.8
91.2
92.7
95.6
97.7
90.8
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
3.1
3
0
5
6
February
5.7
10
3
5
6
March
10.0
12
6
12
11
April
16.2
17
17
17
16
May
21.2
21
21
20
June
28.2
25
29
30
July
30.8
30
32
31
August
30.5
30
32
29
September
27.8
27
29
October
18.0
18
19
November
10.9
13
9
15
December
7.5
8
3
10
Average
17.1
10.2
16.5
18.1
11.7
18.2
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
-9.5
-10
-9
-8
-7
February
-8.8
-4
-8
-10
-8
March
-4.4
-3
-5
-4
-2
April
-1.9
3
0
0
-2
May
7.4
9
6
7
June
12.7
13
13
12
July
16.1
15
18
16
August
15.2
15
16
14
September
11.2
11
12
October
2.7
2
3
November
-4.3
-2
-7
-1
December
-6.1
-4
-9
-6
Average
2.9
-4.5
3.1
2.6
-4.3
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
9.6
10
10
10
9
February
12.4
13
14
10
15
March
10.3
7
10
12
12
April
7.8
8
6
2
10
May
4.0
6
5
2
June
2.9
6
2
3
July
2.8
3
2
3
August
1.3
2
1
1
September
2.4
2
3
October
4.4
7
1
November
6.8
8
7
0
December
6.1
5
14
3
Average
5.8
9.1
6.2
5.1
1.7
6.7
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
11.3
10
10
13
13
February
12.7
11
12
14
14
March
11.8
11
12
13
11
April
14.0
14
12
17
12
May
10.7
10
11
12
June
9.2
8
8
11
July
9.1
8
9
10
August
8.3
9
8
10
September
8.6
9
9
October
10.0
9
11
November
11.9
11
12
12
December
12.9
13
14
12
Average
11.1
11.5
10.1
11.3
11.9
11.4
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
329°
310°
312°
312°
February
310°
305°
313°
322°
March
345°
322°
336°
303°
April
326°
327°
319°
312°
May
164°
317°
123°
June
145°
268°
294°
July
115°
135°
155°
August
302°
166°
149°
September
349°
155°
October
339°
326°
November
321°
324°
313°
December
321°
314°
281°
Prevailing wind direction
Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.