A No-Burn Day in Southern California is a South Coast Air Quality Management District ban on residential wood burning, issued through its Check Before You Burn program. The district declares one when forecasters expect winter weather to trap fine particle pollution near the ground across the South Coast Air Basin. A No-Burn Day has nothing to do with wildfire. It targets smoke from home fireplaces and wood stoves, which becomes a serious source of unhealthy particle pollution when still winter air keeps smoke from spreading out.
What Is a No-Burn Day?
A No-Burn Day is a rule, not a weather event. South Coast AQMD's Check Before You Burn program bans use of residential fireplaces and wood stoves on days when meteorologists forecast unhealthy particle pollution across the South Coast Air Basin. The program is Southern California's own regional rule. It is separate from the Bay Area's "Spare the Air" program, which runs its own winter wood-smoke restrictions.
Why Restrict Fireplaces When No Wildfire Is Burning?
Fireplaces are restricted on calm winter days because the still weather that makes a quiet evening also traps smoke near the ground. On clear, cold, calm nights, a temperature inversion, warm air above cooler air at the surface, can cap the South Coast Air Basin and stop the vertical mixing that normally carries pollution away. Wood smoke is a major source of fine particles, PM2.5. When thousands of homes burn wood on the same still night, the combined smoke can push particle pollution to unhealthy levels with no wildfire anywhere nearby.
Wildfire smoke events work differently, as what is PM2.5, the tiny particles in LA's wildfire smoke explains. A No-Burn Day targets home wood smoke building up under a winter inversion.
Where and When Does the Rule Apply?
The Check Before You Burn rule applies across the South Coast Air Basin, which covers most of the Los Angeles metro area, during the winter wood-burning season from November through February. That is when stagnant air and high PM2.5 are most likely. The district can adjust its season and forecast criteria, so confirm the current season and each day's status on South Coast AQMD's official Check Before You Burn page.
The rule applies the same way near Downtown Los Angeles, Pasadena or Woodland Hills, as long as the location is inside the South Coast Air Basin.
Which Homes or Devices May Be Exempt?
South Coast AQMD exempts some homes and devices, generally households where a wood-burning device is the only adequate source of heat and certain low-emission devices that meet the district's cleaner-burning standards. The district updates these criteria, so confirm current exemptions on South Coast AQMD's website before relying on one. An exemption allows burning under the rule; it does not mean the smoke is healthy for your neighbors.
Is a No-Burn Day a Fire-Weather Alert?
A No-Burn Day is not a fire-weather alert. A No-Burn Day is an air-pollution rule about wood smoke.
A Red Flag Warning is an NWS alert for conditions that favor fast wildfire spread. A local fire agency's burn ban restricts outdoor burning because dry vegetation and wind raise wildfire danger. More than one can be active on the same day for different reasons, so checking one does not tell you the status of the others.
| Product | Issued by | Primary purpose | What to check |
|---|---|---|---|
| No-Burn Day | South Coast AQMD | Reduce residential wood smoke and PM2.5 | Check Before You Burn status and any exemptions |
| Outdoor burn ban | Local fire agency or jurisdiction | Prevent wildfire ignition | Current local restrictions and permit rules |
| Red Flag Warning | National Weather Service | Warn of weather favoring rapid fire spread | Warning polygon, valid time, wind, and humidity |
How Do Residents Check Today's Status?
Check today's No-Burn Day status on South Coast AQMD's official Check Before You Burn page, which the district updates daily during winter based on the forecast. AirNow and South Coast AQMD also publish current PM2.5 AQI readings across the basin, which add context but do not replace the official burn status. For how to read the AQI, see AQI explained for Southern California. For daytime ozone pollution, see ground-level ozone in Southern California.
Before lighting a fireplace or wood stove on a cold Southern California evening, check South Coast AQMD's current Check Before You Burn status and the day's PM2.5 forecast. A chilly, still evening often means burning is banned. WeatherLA's Los Angeles pages track air quality, but South Coast AQMD's Check Before You Burn determination decides whether burning is allowed.