Air quality in Prince George's County, MD

EPA monitor readings, 2021 to 2025 · 967,000 people

A few bad days a yearMostly ozone
Bad-air days a year
5
days with an AQI over 100

About 1 day in 79. That's down from about 36 a year in the early 2000s. Prince George's County has the 3rd most bad-air days of the 16 Maryland counties with monitors.

<1day unhealthy for everyoneAQI over 150, a year
41AQI on a typical dayGood: fine for everyone
May to Julworst monthsOzone on hot afternoons
192worst day since 2016Jun 8, 2023, fine particles
How to read the AQIThe EPA's air score runs from 0 to 500. Higher is worse. Over 100 counts as a bad-air day.
Typical day 41 (Good)Worst day 192 (Unhealthy)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

When bad air happens in Prince George's County

Average bad-air days in each month, from 10 years of daily readings since 2016. Most fall in May, June and July.

Jan0
Feb0
Mar0
Apr0.3
May0.6
Jun1.8
Jul2.0
Aug0.4
Sep0.2
Oct0
Nov0
Dec0
012JanFebMarAprMayJunJulAugSepOctNovDecOZONE SEASON012JFMAMJJASONDOZONE
Fine particles (smoke, soot)Ozone (smog)Bars stack in that order, from the bottom.
See the numbers by month
Average bad-air days a year in each month in Prince George's County, from 10 years of daily readings
MonthOzoneFine particlesAll
January000
February000
March000
April0.300.3
May0.600.6
June1.50.31.8
July2.002.0
August0.400.4
September0.200.2
October000
November000
December000

The worst day since 2016 was June 8, 2023: AQI 192, from fine particles.

What causes it

The pollutant that pushed the AQI over 100 on each of the 53 bad-air days since 2016.

94%ozone
94%Ozone: smog that forms in sunlight on hot days
6%Fine particles: smoke and soot

Most bad days here are ozone days: smog that builds on hot, sunny afternoons.

CDC estimates by month, 2001 to 2022

The CDC's model counts bad-air days at the county's worst spot, from monitors and satellites. Particles (brown) fill the inside of the ring and ozone (blue) the outside.

January: 0.4 smoky days a yearJFebruary: 0.0 smoky days a yearFMApril: 0.8 ozone days a yearAMay: 0.1 smoky days a yearMay: 1.9 ozone days a yearMJune: 0.5 smoky days a yearJune: 5.2 ozone days a yearJJuly: 0.8 smoky days a yearJuly: 5.9 ozone days a yearJAugust: 1.0 smoky days a yearAugust: 5.0 ozone days a yearASeptember: 0.0 smoky days a yearSeptember: 1.3 ozone days a yearSOctober: 0.0 smoky days a yearOctober: 0.0 ozone days a yearONovember: 0.1 smoky days a yearNDecember: 0.0 smoky days a yearDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Prince George's County, 2001 to 2022
MonthFine particlesOzone
January0.40
February00
March00
April00.8
May0.11.9
June0.55.2
July0.85.9
August1.05.0
September01.3
October00
November0.10
December00

What helps in Prince George's County

Most bad days here are ozone, which builds on hot afternoons. Timing helps most; filters don't remove ozone.

Move workouts to the morning

Ozone peaks on hot, sunny afternoons. Mornings are usually cleaner.

Ozone guide →

Check tomorrow's forecast

AirNow posts an air quality forecast by ZIP code, usually the day before.

AirNow →

Keep one room clean on smoky days

Shut the windows and run an air purifier sized for the room.

Choosing a purifier →

For today's reading and tomorrow's forecast, check AirNow by ZIP code. Its fire and smoke map adds smoke plumes.

Purifiers catch smoke but don't remove ozone, and smoky days are rare here. If you want one for wildfire season anyway, see the 3 models we'd buy, each with a verified smoke rating.

Every year since 2000

Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2023, with 11 bad-air days.

0204060802000542005201020152020202530204060802000542010202020253
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Prince George's County
YearBad-air daysOver 150
2000359
20013820
20025427
2003244
2004275
2005408
20064010
20074310
2008221
200940
2010356
2011297
2012236
201360
201440
201571
201690
201760
201881
201960
202010
202150
202210
2023113
202430
202530

Prince George's County and its neighbors

Bad-air days a year, 2021 to 2025. Maryland counties with monitors averaged about 3 bad-air days a year, weighted by population.

Questions people ask about air in Prince George's County

How often is the air bad in Prince George's County?

From 2021 to 2025, monitors in Prince George's County recorded about 5 bad-air days a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2023, with 11 bad-air days.

What causes bad air in Prince George's County?

Most bad days here are ozone days: smog that builds on hot, sunny afternoons. Bad days cluster in May, June and July.

Where can I see today's air quality in Prince George's County?

AirNow, run by the EPA and its partners, shows the current AQI and tomorrow's forecast for your ZIP code. Its fire and smoke map adds smoke plumes. On a typical day the AQI in Prince George's County is about 41, which is good, fine for everyone. Check it most in May, June and July, when bad days here cluster.

About these numbers

Day counts come from the EPA's county air quality summaries, which take the worst reading across a county's monitors each day. Monitors here reported on about 365 days a year from 2021 to 2025. A county is large, and your street can be cleaner or worse. CDC's model, which estimates every county from monitors and satellites, gives the worst spot in Prince George's County almost no high-particle days and about 3 high-ozone days a year from 2018 to 2022.

Sources: EPA AirData county AQI summaries (2000 to 2025) and daily county AQI (2016 to 2025); CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone (2001 to 2022). Updated November 8, 2026.