Ashburn Weather in September
Average highs run from 89°F on September 1 to 84°F on September 30, and lows from 69°F to 61°F.
September day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
September at a glance
- Average high
- 87°F
- Average low
- 65°F
- Record high
- 101°FSep 8, 1990
- Record low
- 37°FSep 30, 1967
- Chance of a freeze
- 0%
- Days of 90°F or more
- 8.9
- Daylight
- 12 h 48 min to 11 h 53 min
- Cloud cover
- 49%
- Humidity
- 75%
- Dew point
- 67°F
- Wind
- 7.6 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| Sep 1 | 89°F | 69°F | 97°F 1998 | 59°F 1946 | 0% | |
| Sep 2 | 89°F | 69°F | 98°F 1943 | 55°F 1903 | 0% | |
| Sep 3 | 89°F | 68°F | 98°F 1944 | 59°F 1954 | 0% | |
| Sep 4 | 89°F | 68°F | 99°F 1944 | 60°F 1952 | 0% | |
| Sep 5 | 89°F | 68°F | 100°F 1944 | 58°F 1967 | 0% | |
| Sep 6 | 89°F | 68°F | 100°F 1999 | 55°F 1984 | 0% | |
| Sep 7 | 88°F | 68°F | 100°F 1941 | 52°F 1984 | 0% | |
| Sep 8 | 88°F | 68°F | 101°F 1990 | 55°F 1965 | 0% | |
| Sep 9 | 88°F | 67°F | 100°F 1990 | 56°F 2011 | 0% | |
| Sep 10 | 88°F | 67°F | 99°F 1939 | 55°F 2011 | 0% | |
| Sep 11 | 88°F | 67°F | 99°F 1954 | 55°F 1976 | 0% | |
| Sep 12 | 88°F | 67°F | 100°F 2002 | 49°F 1940 | 0% | |
| Sep 13 | 87°F | 66°F | 98°F 1991 | 50°F 1967 | 0% | |
| Sep 14 | 87°F | 66°F | 99°F 1991 | 50°F 2015 | 0% | |
| Sep 15 | 87°F | 66°F | 100°F 1991 | 51°F 1967 | 0% | |
| Sep 16 | 87°F | 66°F | 99°F 1980 | 50°F 1967 | 0% | |
| Sep 17 | 87°F | 65°F | 97°F 1942 | 50°F 1961 | 0% | |
| Sep 18 | 87°F | 65°F | 101°F 2019 | 50°F 1903 | 0% | |
| Sep 19 | 86°F | 65°F | 98°F 1942 | 47°F 1981 | 0% | |
| Sep 20 | 86°F | 64°F | 99°F 1997 | 46°F 1981 | 0% | |
| Sep 21 | 86°F | 64°F | 99°F 1990 | 49°F 1984 | 0% | |
| Sep 22 | 86°F | 64°F | 99°F 1940 | 46°F 1983 | 0% | |
| Sep 23 | 86°F | 63°F | 99°F 1940 | 46°F 1983 | 0% | |
| Sep 24 | 85°F | 63°F | 98°F 1905 | 48°F 1967 | 0% | |
| Sep 25 | 85°F | 63°F | 98°F 1905 | 46°F 1990 | 0% | |
| Sep 26 | 85°F | 62°F | 98°F 2019 | 47°F 1975 | 0% | |
| Sep 27 | 85°F | 62°F | 99°F 2019 | 47°F 1975 | 0% | |
| Sep 28 | 84°F | 62°F | 98°F 1904 | 47°F 1947 | 0% | |
| Sep 29 | 84°F | 61°F | 97°F 1904 | 42°F 1967 | 0% | |
| Sep 30 | 84°F | 61°F | 98°F 1904 | 37°F 1967 | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (EDT).
- September 1
- sunrise 7:10 AM, sunset 7:58 PM
- September 30
- sunrise 7:28 AM, sunset 7:21 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00090406 (Ashburn 3 Ene), public domain. Records: NOAA GHCN-Daily, station USC00092266, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.