Wildfire smoke map

What this map is showing

The grey shapes are wildfire smoke plumes from NOAA's Hazard Mapping System (HMS). NOAA analysts look at satellite imagery and hand-draw the outline of visible smoke once a day, grading each plume Light, Medium, or Heavy by how thick it looks from space. It's an expert reading of the satellite picture, not an automatic sensor — and it is dated, so the map shows the newest published analysis and stamps its date (hover or tap a plume to see it).

Grey does not mean smoke at ground level. HMS maps column smoke — smoke anywhere in the sky overhead, often thousands of feet up. A grey area can sit over you while the air you breathe stays clean, and occasionally the reverse. To know what you're actually breathing, check ground-level air quality: the is it smoky near me check below reads the nearest EPA monitor, and the air quality map shows PM2.5 and AQI across the country.

Why does it cover such a huge area? In fire season, smoke rides the wind for hundreds — sometimes thousands — of miles (long-range transport). A single large fire can grey the sky several states downwind, which is why the plumes on the map often dwarf the fires that made them.

Why doesn't the smoke sit on top of the fires? A grey plume is often nowhere near a fire dot on this map. Three reasons, all about how the two layers are drawn:

• Smoke travels. Column smoke drifts hundreds to thousands of kilometres downwind on the prevailing winds, so a plume usually sits well downwind of the fire that produced it — not on top of it.
• The layers cover different areas. The NOAA HMS smoke analysis spans all of North America — including fires in Canada and Mexico — while the fire markers here are US-only (WFIGS incidents and US-filtered NASA FIRMS detections). A heavy plume across the northern tier with no dots beneath it is typically smoke drifting down from Canadian fires we don't plot.
• The layers run on different clocks. HMS is a once-a-day, dated snapshot; the fire detections update continuously over 24 hours. So the smoke outline and the newest fire dots can be hours out of step.

The three shades, per NOAA HMS — a description of the smoke overhead, not a surface reading:

• Light — thin, diffuse smoke in the column; the sky may look only slightly hazy.
• Medium — moderately thick smoke overhead; noticeably hazy skies.
• Heavy — dense, thick smoke in the column; the sun can dim and redden. Even here, whether it's smoky at the surface depends on how much has mixed down — check the AQI.

Column smoke vs. ground-level smoke — read honestly

This is the one thing most smoke maps blur. A satellite looks straight down and flags smoke anywhere in the atmospheric column — often thousands of feet up. That plume can be thick on the map while the air you breathe is fine, because the smoke never mixed down to the surface.

• Satellite smoke (NOAA HMS). An analyst-drawn outline of smoke seen from space, graded light / medium / heavy. It's an analysis of the column, issued once a day — great for tracking where plumes travel, not a live surface reading.
• Ground-level smoke (PM2.5). What EPA monitors measure at breathing height, reported as an AQI. This is what determines whether to close the windows — and it's the number in the "is it smoky near me" check above.
• Fire detections (NASA FIRMS). Satellite heat signatures — the smoke's source. A detection is a heat signal, not a confirmed fire and not a photograph.

Read them together: heavy column smoke on the map plus a high ground AQI means smoke has reached the surface. Heavy column smoke with a low AQI means it's passing overhead — for now.

Smoke map FAQ

What is this map showing exactly?

Wildfire smoke plumes from NOAA's Hazard Mapping System (HMS) — outlines that NOAA analysts hand-draw from satellite imagery once a day, graded Light, Medium, or Heavy — plus NASA's satellite fire detections underneath. The grey shows where smoke is in the sky (the atmospheric column); it is a dated analysis, not a live sensor feed, and not a ground-level reading. Attributed to NOAA/NESDIS HMS and NASA FIRMS.

Does grey mean there is smoke at ground level?

Not necessarily. HMS maps column smoke — smoke anywhere overhead, often high up. A grey area can sit above clean surface air, and sometimes clear skies hide smoke that has settled down. What you breathe is ground-level PM2.5, measured by EPA monitors and reported as AQI — check the is it smoky near me tool above or the air quality map.

Why does the smoke cover such a huge area?

Wildfire smoke travels — in fire season it rides the wind for hundreds or thousands of miles (long-range transport). One large fire can grey the sky several states downwind, so the plume on the map is often far bigger than the fire that produced it. That's per NOAA HMS, which traces the smoke wherever the satellite sees it.

Why doesn't the smoke sit on top of the fires?

Three reasons, all about how the layers are drawn. First, smoke travels: NOAA HMS traces column smoke that drifts hundreds to thousands of kilometres downwind on the prevailing winds, so a plume sits well downwind of its fire, not over it. Second, the layers cover different areas — the HMS smoke analysis spans all of North America (including Canadian and Mexican fires), while the fire dots here are US-only (WFIGS incidents and US-filtered NASA FIRMS). A heavy plume over the northern states with no dots under it is usually smoke carried down from fires in Canada that we don't plot. Third, the layers run on different clocks: HMS is a once-a-day dated snapshot, while the fire detections update continuously through the day. All attributed to NOAA HMS (smoke) and WFIGS / NASA FIRMS (fires).

Why is there smoke in the air today near me?

Smoke you're seeing usually came from fires that can be hundreds of miles away — wildfire smoke travels across states on the wind. Find the source on the map above (the fire detections and their plumes), and confirm the ground-level impact with the "is it smoky near me" check. If the sky is hazy but the AQI is low, the plume is aloft, not at the surface.

When will the smoke clear?

Honestly, that depends on the wind and the fire, and we won't guess. Smoke clears when the wind shifts the plume away or the source fire is contained. This map relays observed conditions, not forecasts — for the next-day outlook, see the smoke forecast, which carries AirNow's AQI forecast for your area and NOAA's HRRR-Smoke plume graphics.

Is this a live satellite smoke map?

Yes — the smoke layer is NOAA's satellite Hazard Mapping System (HMS) analysis, and the fire layer is NASA's near-real-time satellite detections (FIRMS). HMS is issued as a dated analysis, so the map shows the newest available product and stamps its date; if today's isn't published yet, it falls back to the most recent one.

Is the smoke bad for my health?

Wildfire smoke's main hazard is fine particle pollution (PM2.5). We relay EPA's AQI category and its official meaning — we don't give personal medical advice. For who's most at risk and the EPA's protective steps, see wildfire smoke & health; for the AQI scale itself, the air quality map.