How to Track Wildfire Smoke and Air Quality Near You

Wildfire smoke does not stay near the fire. It can drift across states, settle into valleys overnight and clear by afternoon, or the reverse. A clear morning can turn hazy by lunch. For families, outdoor workers, travelers and anyone with health concerns, knowing how to check air quality quickly has become an everyday skill during fire season.

This guide explains the Air Quality Index, where reliable data comes from, and how to build a routine that fits your life. It is general information, not medical advice. If you or someone in your household has heart or lung conditions, is pregnant, or is caring for young children or older adults, follow your doctor's guidance about smoke.

How the Air Quality Index works

In the United States, air quality is reported using the Air Quality Index (AQI), a scale from 0 to 500 with color-coded categories:

• 0 to 50, green: Good.
• 51 to 100, yellow: Moderate.
• 101 to 150, orange: Unhealthy for Sensitive Groups.
• 151 to 200, red: Unhealthy.
• 201 to 300, purple: Very Unhealthy.
• 301 and higher, maroon: Hazardous.

The higher the number, the greater the health concern. For wildfire smoke, the pollutant that matters most is usually fine particulate matter, called PM2.5: particles small enough to be inhaled deeply into the lungs.

Where reliable smoke and fire data comes from

• AirNow, run by the U.S. Environmental Protection Agency with state, local and tribal partners, reports official air quality readings and forecasts at airnow.gov. Its Fire and Smoke Map combines official monitors, corrected readings from low-cost sensors, smoke plume outlines and fire locations.
• The National Weather Service issues fire weather watches and red flag warnings when weather conditions such as wind, low humidity and dry fuels make fire spread more likely.
• State and local air agencies often publish smoke advisories and local guidance.
• Fire agencies such as the National Interagency Fire Center and state fire departments publish incident information.
• Satellite fire detections from sources like NASA's FIRMS show heat signatures detected from space. They are helpful for spotting new activity, but a detection is approximate and does not show an exact fire perimeter.

Official monitors and low-cost sensors

You may notice that a neighborhood sensor shows a different number than the nearest official monitor. Official monitors use standardized, regulatory-grade equipment but are spread far apart. Low-cost sensors are much more common and show local variation, but they need correction to be comparable, and individual sensors can be inaccurate. Maps that apply corrections, like the AirNow Fire and Smoke Map, give a useful combined picture.

A simple checking routine

During fire season, a few habits keep you informed without constant worry:

1. Check the AQI each morning and again before outdoor plans, such as a run, a youth soccer game or a long drive.
2. Look at the forecast, not just the current reading, since smoke often shifts with wind and time of day.
3. Set up alerts in an air quality app or service you trust so you hear about changes without checking constantly.
4. Watch for fire weather watches and red flag warnings in your area and in places you plan to travel.
5. Know your local health guidance for each AQI level, especially for sensitive members of your household.

Preparing your home for smoky days

Public health and environmental agencies commonly recommend a few steps for smoky periods. Keep windows and doors closed when outdoor air is poor. Consider a portable air cleaner with a HEPA filter sized for the room where you spend the most time, and if you have central heating and air, ask whether your system can use a higher-efficiency filter. Avoid adding indoor pollution from sources like candles or frying. Check with your doctor about what is right for your household.

Traveling and camping during fire season

RV travelers, campers and people visiting family face an extra challenge: conditions at your destination may be very different from home. Before and during trips, check air quality and fire information for each stop, save the locations of where you will stay, and know the official alert systems for the counties you pass through. Our guide on making sure emergency alerts reach your phone explains how wireless alerts follow you as you travel.

Where Swift Warning fits

We build Swift Warning, a mobile app that watches public feeds for natural dangers around the places you save, such as home, work, family property, campsites and RV stops. For wildfire today, it draws on sources including WildCAD, NIFC, CAL FIRE, NASA FIRMS, the National Weather Service and AirNow, and shows smoke and air quality alongside fire incidents and fire-weather watches. Wildfire dispatch information from 43 Western dispatch centers is checked every 45 seconds by default, which is a polling interval rather than a promised alert time.

Swift Warning is an independent app, not a government service. Always follow official alerts and instructions from local authorities.

Frequently asked questions

What AQI level is safe for outdoor activity?

AirNow publishes activity guidance for each category. In general, sensitive groups are advised to reduce prolonged or heavy outdoor exertion starting at the orange level, and everyone at the red level and above. Follow your local health officials and your doctor's advice.

Why does my local sensor show a different reading than the official monitor?

They use different equipment and may be miles apart, and smoke can vary block by block. Low-cost sensors also need correction to match official measurements, so use maps that apply those corrections when possible.

Is a red flag warning the same as an evacuation order?

No. A red flag warning means weather conditions favor rapid fire spread. Evacuation orders come from local authorities, so watch for official alerts and follow their instructions.