Washington Air Quality in July

Across 2019–2025, Washington's July air quality had a median AQI of 61 (Moderate) over 217 monitored days in the Washington-Arlington-Alexandria, DC-VA-MD-WV area. 11.1% of July days (24 of 217) reached Unhealthy for Sensitive Groups or worse, and ground-level ozone set the daily AQI on 53.0% of days. The cleanest July on record here was 2022 (median AQI 58, 1 day above 100) and the worst was 2023 (median 64, 7 days above 100, peak AQI 131).

61
Median AQI
Moderate
11.1%
Days above AQI 100
24 of 217 days
103
90th percentile AQI
worst 1 day in 10
185
Peak AQI
Unhealthy
O3
Main pollutant
53.0% of days
20.7%
Good days
45 of 217
  • Good: 20.7%
  • Moderate: 68.2%
  • Unhealthy for Sensitive Groups: 8.8%
  • Unhealthy or worse: 2.3%

Improve Indoor Air Quality

Even with good outdoor air in Washington, indoor PM2.5, dust and allergens build up. A True-HEPA purifier keeps a bedroom or office consistently clean.

Recommended: Levoit Core 400STrue HEPA · CADR ~141 CFM · rooms up to 219 sq ft

Check Price on Amazon →

As an Amazon Associate, we earn from qualifying purchases.

QUICK ANSWER

How is the air in Washington in July?

Moderate on a typical day: median AQI 61 across 2019–2025, with 11.1% of July days above AQI 100. Ground-level ozone is the main driver.

  • 20.7% of July days were Good (AQI 0–50), 68.2% Moderate (51–100).
  • 24 days of 217 reached AQI 101+; the July peak was 185.
  • Best July: 2022; worst July: 2023.

Frequently asked questions

What is the air quality like in Washington in July?

Across 2019–2025, the median daily AQI in Washington in July was 61 (Moderate). 20.7% of days were Good, 68.2% Moderate, and 11.1% reached Unhealthy for Sensitive Groups or worse, based on 217 monitored days in EPA's Air Quality System.

Is July a good time for outdoor exercise in Washington?

A typical July day in Washington is Moderate (median AQI 61): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 9 of July days (11.1%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.

Which pollutant causes Washington's July air quality problems?

Ground-level ozone set the daily AQI on 53.0% of July days in Washington. The highest July AQI recorded in 2019–2025 was 185 (Unhealthy), in 2023.

Washington July air quality, year by year

Washington July air quality by year (Washington-Arlington-Alexandria, DC-VA-MD-WV, EPA AQS daily AQI)

YearDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
201931644159O3
202031573171O3
202131674153PM2.5
2022cleanest31581128PM2.5
2023worst31647131O3
202431631105O3
202531554185PM2.5

What July air means in Washington

A typical July day in Washington is Moderate (median AQI 61): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 9 of July days (11.1%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.

July's median AQI of 61 is above Washington's whole-year median of 52, making it one of the area's dirtier periods. Nationally, the median July AQI across every EPA metro area (103,858 metro-days, 2019–2025) is 47, so Washington runs above the national July norm; 11.1% of its July days topped AQI 100 versus 3.6% nationally (above average).

July is part of Washington's summer season (June, July, August); the summer page pools all three months.

Activity-specific thresholds: running, cycling, kids' sports.

Right now in Washington

The latest EPA AirNow observation puts Washington's AQI at 41 (PM2.5). The figures above are multi-year month statistics, not today's reading.

View current Washington air quality →

Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Washington-Arlington-Alexandria, DC-VA-MD-WV), 2019–2025. Daily AQI per CBSA is the highest AQI reported by any monitor in the area that day; the defining parameter is the pollutant that set it. Month and season statistics pool every such day in the period across all years listed. Retrieved 2026-09-09.