Air quality in St. Bernard Parish, LA

EPA monitor readings, 2021 to 2025 · 44,000 people

A few bad days a yearMostly ozone
Bad-air days a year
1
day with an AQI over 100

5 bad-air days in 5 years of readings, 2021 to 2025. That's down from about 14 a year in the early 2000s. St. Bernard Parish is tied with 4 other Louisiana counties for the 7th fewest bad-air days of the 19 with monitors.

0days unhealthy for everyoneAQI over 150, a year
47AQI on a typical dayGood: fine for everyone
Jan, May and Junworst monthsOzone on hot afternoons
138worst day since 2016Jan 1, 2024, 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 47 (Good)Worst day 138 (Unhealthy for sensitive groups)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

When bad air happens in St. Bernard Parish

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

Jan0.1
Feb0
Mar0
Apr0
May0.5
Jun0.2
Jul0.1
Aug0.1
Sep0
Oct0
Nov0
Dec0.1
012JanFebMarAprMayJunJulAugSepOctNovDec012JFMAMJJASOND
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 St. Bernard Parish, from 10 years of daily readings
MonthOzoneFine particlesAll
January00.10.1
February000
March000
April000
May0.500.5
June0.200.2
July0.100.1
August0.100.1
September000
October000
November000
December00.10.1

The worst day since 2016 was January 1, 2024: AQI 138, from fine particles (New Year's fireworks are a common cause).

What causes it

The pollutant that pushed the AQI over 100 on each of the 11 bad-air days since 2016.

82%ozone
82%Ozone: smog that forms in sunlight on hot days
18%Fine particles: smoke and soot

The rare bad days here are mostly 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: 0.3 smoky days a yearJanuary: 0.0 ozone days a yearJFMarch: 0.2 ozone days a yearMApril: 0.0 smoky days a yearApril: 1.1 ozone days a yearAMay: 1.9 ozone days a yearMJune: 0.0 smoky days a yearJune: 1.9 ozone days a yearJJuly: 0.5 ozone days a yearJAugust: 0.6 ozone days a yearASeptember: 0.1 smoky days a yearSeptember: 1.0 ozone days a yearSOctober: 0.0 smoky days a yearOctober: 0.8 ozone days a yearONovember: 0.0 smoky days a yearNovember: 0.0 ozone days a yearNDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in St. Bernard Parish, 2001 to 2022
MonthFine particlesOzone
January0.30
February00
March00.2
April01.1
May01.9
June01.9
July00.5
August00.6
September0.11.0
October00.8
November00
December00

What helps in St. Bernard Parish

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 2 bad-air days.

051015202530352000272005201020152020202505101520253035200027201020202025
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in St. Bernard Parish
YearBad-air daysOver 150
2000274
2001120
2002101
2003143
200491
2005141
200670
2007110
200810
200920
201080
201170
201210
201310
201450
201500
201620
201700
201830
201910
202000
202100
202210
202320
202420
202500

St. Bernard Parish and its neighbors

Bad-air days a year, 2021 to 2025. Louisiana counties with monitors averaged about 2 bad-air days a year, weighted by population.

Questions people ask about air in St. Bernard Parish

How often is the air bad in St. Bernard Parish?

From 2021 to 2025, monitors in St. Bernard Parish recorded about 1 bad-air day a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2023, with 2 bad-air days.

What causes bad air in St. Bernard Parish?

The rare bad days here are mostly ozone days: smog that builds on hot, sunny afternoons. Bad days cluster in January, May and June.

Where can I see today's air quality in St. Bernard Parish?

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 St. Bernard Parish is about 47, which is good, fine for everyone. Check it most in January, May and June, 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 364 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 St. Bernard Parish almost no high-particle days and almost no 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.