Click on a day for an hourly weather forecast
The temperatures in Ashburn in September are comfortable with low of 17°C and and high up to 27°C.
You can expect about 3 to 8 days of rain in Ashburn during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Ashburn in September 2025.
If you’re planning to visit Ashburn in the near future, we highly recommend that you review the 14 day weather forecast for Ashburn before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 6° / -1° | 8 | 16 | 8 | 144 mm | Awful | Ashburn in January |
| February | 8° / 1° | 8 | 13 | 8 | 204 mm | Awful | Ashburn in February |
| March | 14° / 5° | 9 | 19 | 3 | 172 mm | Bad | Ashburn in March |
| April | 19° / 10° | 9 | 21 | 1 | 190 mm | Ok | Ashburn in April |
| May | 25° / 15° | 10 | 21 | 0 | 204 mm | Good | Ashburn in May |
| June | 29° / 19° | 10 | 20 | 0 | 225 mm | Ok | Ashburn in June |
| July | 30° / 21° | 12 | 19 | 0 | 262 mm | Ok | Ashburn in July |
| August | 30° / 20° | 10 | 21 | 0 | 227 mm | Ok | Ashburn in August |
| September | 27° / 17° | 7 | 23 | 0 | 161 mm | Good | Ashburn in September |
| October | 20° / 11° | 6 | 25 | 0 | 147 mm | Good | Ashburn in October |
| November | 13° / 5° | 6 | 23 | 1 | 118 mm | Ok | Ashburn in November |
| December | 9° / 2° | 8 | 19 | 4 | 172 mm | Awful | Ashburn in December |