Generally, the weather in Washington DC right through September is 20. High temperatures are around 27 and typical average low being around 17 degrees. Find more information below:
| Month | Degrees Celsius |
|---|---|
| Temperature | 20 |
| High Temperature | 27 |
| Low Temperature | 17 |
| Sunshine Per Day | 9 |
Useful Links: Washington DC Weather: Average Weather & Yearly Climate