Early autumn · Weather & things to do
Washington, DC in September
Washington, DC cools off: highs slip to 80°F (27°C), from 87°F in August, with lows of 62°F (16°C) and about 4.2 in (107 mm) of rain.
September opens the best stretch on our comfort score, at 83/100 (3rd of 12).
- Avg high
- 80°F (27°C)
- Avg low
- 62°F (16°C)
- Rain
- 4.2 in (107 mm)
- Humidity
- 72%
- Cloud cover
- 52%
- Daylight
- ~12 h 14 min
- Comfort score
- 83/100 · Great
What September feels like
Days are warm, averaging 80°F (27°C), easy weather for being outside from morning to evening.
Lows average 62°F (16°C).
Showers are part of the month, adding up to about 4.2 in (107 mm).
Plan around September
September is one of Washington, DC's best months on the climate data.
- Last warm month for a while: October highs fall to 68°F.
- Opens the best-scoring stretch on our comfort score: April & May and September & October.
- Comfort improves from 70/100 in August to 83/100.
- Our Capital Cities Corridor route recommends Mar – Jun, so September falls outside its suggested window.
What to pack for September
- Light, breathable clothes80°F afternoons
- Packable rain jacket or umbrellaabout 4.2 in of rain
- Comfortable walking shoesmost picks involve some walking
What to do in Washington, DC in September
September is good outdoor weather here, so these picks lean toward the open air.
U.S. Capitol Visitor Center
Free guided tours of the Capitol Rotunda and crypt.
National Gallery of Art
Free galleries including the only Leonardo da Vinci painting in the Americas.
Old Ebbitt Grill
Historic saloon next to the White House, known for its oyster bar.
National Museum of African American History and Culture
Smithsonian museum tracing African American history from slavery to today.
Ben's Chili Bowl
U Street landmark since 1958, known for the chili half-smoke.
Why now September scores 83/100 for comfort, good conditions for being outside.
Nearby in September
- Baltimore in September~35 mi · highs 80°F, 4.4 in rain · similar daytime temperatures, about as wet
- Lancaster in September~87 mi · highs 79°F, 4.6 in rain · similar daytime temperatures, about as wet
- Kennett Square in September~96 mi · highs 79°F, 4.4 in rain · similar daytime temperatures, about as wet
- Richmond in September~97 mi · highs 82°F, 4.6 in rain · 1°C (2°F) warmer by day, about as wet
These averages also cover Georgetown and National Mall & Downtown.
NASA POWER 2001–2025 monthly averages on a ~50 km grid. Comfort scores weigh temperature, rain, humidity and cloud: see how we score each month. Check a forecast before you go.
Washington, DC in September: quick answers
Is September a good time to visit Washington, DC?
Yes. On the climate data it's one of the best months, scoring 83/100. Expect highs of 80°F (27°C) and 4.2 in (107 mm) of rain. Our Capital Cities Corridor route recommends Mar – Jun, so September is outside its suggested window.
How hot is Washington, DC in September?
Average highs are 80°F (27°C) and average lows 62°F (16°C), making it the 4th-warmest month by daytime highs.
Does it rain a lot in Washington, DC in September?
Some: about 4.2 in (107 mm) of rain falls across September on average, the 5th-wettest month of the year. The annual total is about 45.4 in (1152 mm).
What should I pack for Washington, DC in September?
Bring light, breathable clothes (80°F afternoons), packable rain jacket or umbrella (about 4.2 in of rain) and comfortable walking shoes (most picks involve some walking).
Planning Washington, DC in September?
Plan it together in TripsCircle: one itinerary, one shared packing list and costs split as you go.