United States
Washington, D.C. in September
🍂 AutumnPleasant and some showers.
🎒 Pack: compact umbrella or rain jacket
Why September scores 9.0What goes into the score
How it works- Weather comfort9.1
- ✓Comfortable temperatures (27°C highs / 18°C lows)
- ✓Slightly humid (dew point 15.8°C)
- !Wet: ~100 mm rain, ~3 heavy-rain days
- Air quality8.7
- ✓Good (within WHO guideline) (PM2.5 ~13 µg/m³)
- Seasonal hazards10.0
- ·No notable seasonal hazards
- Safety baseline7.5
- ·Increased caution
| Sep | May | |
|---|---|---|
| Score | 9.0 Excellent | 9.2 Excellent |
| Season | 🍂 Autumn | 🌷 Spring |
| High / low | 27° / 18° | 25° / 14° |
| Rain | 100 mm | 100 mm |
| Humidity | dew pt 16° | dew pt 14° |
| PM2.5 | 13 µg/m³ | 10 µg/m³ |
Typical-month data: NASA POWER (MERRA-2 reanalysis) 2015–2024 (modelled, not a forecast). Temperatures: Washington, D.C. weather-station normals. Rainfall: Washington, D.C. weather-station normals (national met service).
Holidays & crowdsSeptember 2027
Long weekendThere's at least one long weekend. Domestic travel picks up and popular spots get busier over those days.
- Labor Day 4–6 Sep · 3 days off in a row
National holidays only; regional holidays and school breaks aren't included. Source: holidays (open-source public-holiday calendar).
Nature calendarBlossoms, leaves & seasons in Washington, D.C.
- Cherry blossom (Tidal Basin)Typical datesPeak bloom usually last week of March to first week of April
Peak bloom has ranged from 15 Mar (1990) to 18 Apr (1958). In 2026 peak bloom was reached on 26 Mar.
Source: US National Park Service
- Snowy daysTypical datesSnow likely Dec–Mar (most in Jan: ~3 days)
Average number of days with snowfall at Washington, D.C.. About 12 cm of snow falls in an average Jan.
Source: Washington, D.C. weather-station normals (national weather service, via Wikipedia climate table)
Explore Washington, D.C.Events, sights, food & souvenirs
Check event dates locallyThe US capital on the Potomac, known for the National Mall's monuments, free Smithsonian museums and government landmarks.
No major events on our calendar for September.
Coming up later
National Cherry Blossom FestivalDate variesUsually late March to mid-April
Celebrates the blooming of cherry trees gifted by Japan in 1912.
Why go: Peak bloom varies; go at sunrise to avoid crowds.
Where: Tidal Basin
Smithsonian Folklife FestivalDate variesUsually late June to early July
An outdoor festival of living cultural traditions.
Why go: Free; hot and humid in summer.
Where: National Mall
Independence DayEvery year4 July every year
Parade, concert and fireworks on the Mall.
Why go: Security checkpoints and huge crowds.
Where: National Mall
National Mall
A long park lined with monuments including the Lincoln Memorial and Washington Monument.
Smithsonian museums
Free museums such as Natural History, Air and Space and African American History and Culture.
💡 Some popular museums require free timed passes.
US Capitol
The seat of Congress, with guided tours from the visitor centre.
Lincoln Memorial
The temple-style memorial with a seated statue of Abraham Lincoln.
Georgetown
A historic neighbourhood with row houses, shops and a canal path.
Arlington National Cemetery
The military cemetery across the Potomac.
Half-smoke
A spicy pork and beef sausage, a DC specialty.
💡 Ben's Chili Bowl on U Street
Ethiopian food
DC has one of the largest Ethiopian communities in the US.
💡 U Street and Shaw
Maryland crab cakes
Crab cakes from the Chesapeake Bay tradition.
💡 Seafood restaurants and the Wharf
Mumbo sauce
A sweet-sour sauce on wings, a local favourite.
💡 Carry-outs
Smithsonian museum shop items
Books and science or history-themed gifts.
💡 Museum shops
Political memorabilia
Souvenirs themed on the White House, Congress and presidents.
💡 Union Station and museum shops