Verdict: Excellent month
Washington, D.C. Weather in September
September hits the sweet spot in Washington, D.C. — highs around 26°C (79°F), ideal for a full day on foot. Expect showers on roughly 11 days of the month — rarely trip-ruining, worth planning around. Overall, September is one of the best months of the year to be in Washington, D.C..
Average high
26°C / 79°F
Average low
16°C / 61°F
Rain days
~11
Precipitation
134 mm
What to pack for Washington, D.C. in September
- Summer clothes, plus one light layer for air-con and evenings
- A packable rain shell or compact umbrella earns its space
- Comfortable walking shoes — every guide on this site assumes you'll use them
September against the rest of the year
Warmest in Washington, D.C.: Jul (32°C / 90°F) · Coolest: Jan (7°C / 45°F) · Wettest: Aug (~16 rain days)
7°
-1°
Jan
10°
0°
Feb
14°
4°
Mar
19°
8°
Apr
23°
12°
May
29°
18°
Jun
32°
21°
Jul
30°
20°
Aug
26°
16°
Sep
20°
11°
Oct
14°
5°
Nov
9°
1°
Dec
Daily highs / lows in °C · bars show rain days per month · ERA5 climate normals (2020–2024)