Ozone and PM2.5 Air Quality Index (AQI) Forecast

Issued: Sunday, September 20, 2026, 2:30 PM

Sunday, calm to light southerly winds will inhibit dispersion, allowing thin smoke and other pollutants to remain over the state. In addition, mostly sunny and hot conditions will be conducive for ozone production. Thus, AQI levels will be low- to mid-Moderate in most cities, with high-Moderate AQI levels expected in Baton Rouge. Monday, light winds through midday will continue to limit pollutant dispersion. In addition, partly to mostly sunny skies and very warm temperatures will support ozone formation. However, as a weak cold front advances southward into Louisiana, scattered afternoon thunderstorms will enhance mixing and reduce ozone production. Therefore, AQI levels will be low- to mid-Moderate. Tuesday, lingering thunderstorm activity will continue to limit ozone production. However, periods of sunshine and temperatures in the mid-90s will enhance ozone formation over much of the state. Additionally, calm to light north-northeasterly winds will allow thin smoke and other pollutants to linger over the region. These conditions will keep AQI levels low- to mid-Moderate in most cities.

Baton Rouge

 Sunday Monday Tuesday
Ozone 100 - Moderate 77 - Moderate 64 - Moderate
PM25 53 - Moderate 53 - Moderate 50 - Good

Alexandria

 Sunday Monday Tuesday
Ozone 51 - Moderate 58 - Moderate 51 - Moderate
PM25 55 - Moderate 53 - Moderate 50 - Good

Lake Charles

 Sunday Monday Tuesday
Ozone 51 - Moderate 58 - Moderate 51 - Moderate
PM25 39 - Good 44 - Good 39 - Good

Lafayette

 Sunday Monday Tuesday
Ozone 61 - Moderate 51 - Moderate 48 - Good
PM25 33 - Good 50 - Good 44 - Good

Monroe

 Sunday Monday Tuesday
Ozone 51 - Moderate 54 - Moderate 51 - Moderate
PM25 55 - Moderate 53 - Moderate 50 - Good

New Orleans

 Sunday Monday Tuesday
Ozone 67 - Moderate 67 - Moderate 61 - Moderate
PM25 50 - Good 53 - Moderate 50 - Good

Shreveport

 Sunday Monday Tuesday
Ozone 51 - Moderate 67 - Moderate 71 - Moderate
PM25 56 - Moderate 55 - Moderate 50 - Good

Thibodaux

 Sunday Monday Tuesday
Ozone 50 - Good 51 - Moderate 58 - Moderate
PM25 44 - Good 50 - Good 44 - Good

More Information About Understanding AQI Information

The AQI is an index for reporting daily air quality. It tells you how clean or unhealthy your air is, and what associated health effects might be a concern. The AQI focuses on health effects you may experience within a few hours or days after breathing unhealthy air. The following chart provides information regarding the AQI determinations:

Category AQI Value What This Means
Good 0-50 Air quality is considered satisfactory, and air pollution poses little or no risk.
Moderate 51-100 Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
Unhealthy for Sensitive Groups 101-150 Members of sensitive groups may experience health effects. The general public is not likely to be affected.
Unhealthy 151-200 Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects.
Very Unhealthy 201-300 Health warnings of emergency conditions. The entire population is more likely to be affected.
Hazardous 301-500 Health alert: everyone may experience more serious health effects.

Any questions about interpreting this monitoring data should be directed to the DEQ Customer Services Section at 1-866-896-5337.

TO REPORT ENVIRONMENTAL CONCERNS, INCLUDING ODORS, CONTACT THE DEQ SINGLE POINT OF CONTACT (SPOC) - 225-219-3640 or Toll Free 1-888-763-5424. In the event of an environmental emergency, citizens are encouraged to first contact their local authorities - police, sheriff, fire department, etc. Otherwise citizens and the regulated community can contact the SPOC line to report environmental concerns during business hours, 8 a.m. - 4:30 p.m., Monday through Friday at the number listed above. To report a concern outside of business hours call 225-342-1234 or the toll free number. Concerns include spills, releases, odors, fish kills, open burning, waste tires and any other types of environmental incidents. Citizens can report the incident online.

The data has not been quality reviewed or validated. Continuous PM2.5 readings shown are not NAAQS comparable.