Sacramento wildfire smoke forecast
The map above shows NOAA HRRR-Smoke near-surface PM2.5 for the next 48 hours, updated hourly, with active fires from NIFC and live AQI from EPA AirNow monitors. It opens over Sacramento.
Sacramento sits near 30 feet of elevation at the confluence of the Sacramento and American rivers, in the northern Central Valley. The valley is a long, flat trough walled by the Coast Range and the Sierra Nevada, and it is the most persistent smoke trap in California because there is no terrain inside it to break up a settled layer.
Where the smoke comes from
Sierra Nevada fires to the east and Coast Range fires to the west both feed the valley, and smoke from fires well to the north drifts down it. The valley's own agricultural and urban PM2.5 sits underneath, so wildfire smoke stacks on top of a baseline that is already higher than the coast's.
How long it lasts
The Delta breeze is the mechanism. Marine air pushes through the Carquinez Strait from San Francisco Bay most summer afternoons and ventilates the valley from the southwest. When a ridge shuts the Delta breeze off, smoke has nowhere to go and concentrations climb for days without any new fire growth. Watching for the breeze to return is more predictive than watching containment numbers.
Past smoke events
The November 2018 Camp Fire, burning around Paradise about 80 miles north, held Sacramento in unhealthy-to-hazardous air for roughly two weeks and closed schools across the region. August 2020's LNU and northern complexes produced a similar stretch.
Running, riding, and trailheads
The American River Parkway is the region's main running and riding corridor and runs along the valley floor, so it offers no elevation escape at all. The Sierra foothills east of Folsom are the nearest ground that can sit above a shallow valley layer.
Reading the map
Use the layer toggle to compare NOAA HRRR-Smoke with the ECCC FireWork model. When the two disagree, treat the higher reading as the cautious call.
Near-surface is the product that maps to what you breathe and to AQI, not the high-altitude column that only tints the sunset. A sky that looks bad and a monitor that reads fine are usually both correct, and they are describing different layers of air.