Air Quality in Berkeley, California — Live
Live readings from PurpleAir sensors across Berkeley — with free alerts the moment the air turns.
AQI 38 from 5 PurpleAir sensors · Holding steady · data from PurpleAir
As of , the air quality in Berkeley, California is AQI 38 — Good and holding steady — with PM2.5 at 6.8 µg/m³, the median of 5 live PurpleAir sensors reading 36 to 53. Canairy's verdict: Breathe easy.
For scale, that PM2.5 reading is below the World Health Organization's 24-hour guideline of 15 µg/m³. The WHO figure is a daily average and this is a live reading, so read it as a sense of magnitude rather than a formal exceedance — a brief spike and a bad day are not the same thing. More on the WHO guidelines
Pollen today in Berkeley: weeds pollen is the strongest of the three at a low level, from Google's pollen forecast. Canairy shows the tree, grass and weed forecast beside the air reading on every plan, including the free one.
Free to download · Live data from PurpleAir & public monitors
Live PurpleAir sensor map for Berkeley and Oakland, Albany, Emeryville, El Cerrito. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Berkeley
The sensors Canairy reads in Berkeley are 17 AQI points apart right now, from Good to Moderate, which is the whole reason one city-wide number can mislead you: the median describes air you may not be standing in.
| From city center | AQI | Category |
|---|---|---|
| 1.5 mi NE | 49 | Good |
| 1.5 mi W | 53 | Moderate |
| 2.8 mi ESE | 38 | Good |
| 3.8 mi ESE | 39 | Good |
| 5.4 mi SSE | 36 | Good |
Berkeley is a narrow city that climbs from the bay shore to a ridge, and that is the single most useful thing to know about its air. The flats along Interstate 80 and the hill neighbourhoods below Grizzly Peak sit roughly 1,600 feet apart in elevation and can genuinely be in different air on the same afternoon. The city's two real risks come from opposite directions: fire coming over the ridge from the east on a dry wind, and industry up the shoreline to the north.
What Canairy does for Berkeley
A clear verdict
Not just a number — a plain-English call for Berkeley: open the windows, or keep them shut.
Smoke alerts
A push or text the moment the air crosses your threshold — and again when it clears.
A heads-up before it's bad
Trend alerts catch the air turning, so you can close up the house before the smoke settles in.
Every place you care about
Home, work, the kids' school — across Berkeley or across the country, on one screen.
Berkeley's own fire was 1923, and the 1991 one is named for Oakland
On 17 September 1923 a fire that started in the chaparral of Wildcat Canyon was pushed over the ridge by a strong, gusty, intensely dry north-easterly wind and burned into the city itself. It destroyed 640 structures, 584 of them houses, tearing through the La Loma Park and Northside neighbourhoods above the university and heading down Shattuck Avenue toward downtown. It stopped when the north-easterly died and cooler sea air came back in off the bay. That is the pattern that still governs fire weather here: an offshore wind from the north-east is the dangerous one, and the return of the sea breeze is what ends it.
The 1991 firestorm is the one people remember, and it is worth being accurate about it. Cal Fire's official name is the Tunnel Fire; it is commonly called the Oakland Hills firestorm because most of it burned in northern Oakland, though it also burned in south-eastern Berkeley. It ran from 19 to 23 October 1991 over 1,520 acres, killed 25 people, injured 150, and destroyed 2,843 single-family homes plus 437 apartments and condominiums. It carries Oakland's name for a reason, but the ridge it burned along is the same ridge that overlooks Berkeley.
The refinery is up the shoreline, and the advisories usually stop short of Berkeley
The Chevron refinery in Richmond sits a few miles north-west of the UC Berkeley campus, and people here notice when it flares. On 6 August 2012 at 6.15pm a major fire there triggered a community warning, a five-hour shelter-in-place order, and thousands of people seeking medical treatment. It is a checkable event, so check what it actually covered: the shelter-in-place applied to Richmond, North Richmond, San Pablo and El Cerrito. Berkeley was not in it, though black smoke was visible over parts of the East Bay. Air District sampling afterwards found acrolein at 3.2 parts per billion in one sample with seven others below levels of concern, and concluded that the health effects people reported were most likely from smoke particles rather than the specific toxic compounds measured.
The same holds for the flaring that still happens. When the Air District issued an air quality advisory for Chevron Richmond flaring on 31 May 2025, it named Richmond, San Pablo, Pinole and Hercules along with parts of Solano County. Berkeley again was not on the list. The fair summary is that the refinery is close enough to see and occasionally smell from north Berkeley, and that the measured impacts of its worst days have landed north of here rather than on the city. If that ever changes on a particular day, the sensors north of University Avenue are where it would show up first.
The flats and the hills are two different places for air
West Berkeley sits between the bay and Interstate 80, on a corridor Alameda CTC describes as one of the busiest in the Bay Area, carrying as many as 270,000 vehicles a day across the twenty miles between the Carquinez and Bay bridges. The rebuild of the Gilman Street interchange in north-west Berkeley cites volumes approaching 300,000 a day in places. Traffic pollution drops off quickly with distance from the roadway, so an address near Gilman or Ashby and one up in Elmwood are not measuring the same thing.
Elevation splits it further. Central Berkeley sits around 171 feet above sea level; Grizzly Peak on the eastern boundary is 1,754 feet. When a layer of warm air settles over cool marine air, the resulting inversion acts as a lid, and the flats can stay hazy while hillside streets sit above it in clearer air. During a regional smoke event this can reverse, so the practical advice is the same either way: watch the sensor nearest your own elevation and your own block, not a single number for the city.
Berkeley air quality FAQ
What is the air quality in Berkeley right now?
As of September 10, 2026 at 2:12 PM PDT, the air quality in Berkeley, California is AQI 38 — Good — with PM2.5 at 6.8 µg/m³, the median of 5 live PurpleAir sensors. Open the windows. Great for outdoor activity.
Why is there smoke in Berkeley today?
Most of the time it has blown in from a fire well outside the city, somewhere else in Northern California, and settled over the East Bay. Occasionally it is much closer: the hills on Berkeley's eastern boundary are grass and chaparral, and a dry north-easterly wind is the condition that has driven fire over that ridge before, in 1923 and again in 1991. On a cold, still winter evening a low haze is more likely to be wood smoke from fireplaces. The live number on this page will tell you within minutes which situation you are in.
Does the Chevron Richmond refinery affect Berkeley's air?
Less than people assume, based on what has actually been measured. The refinery is a few miles north-west of the UC Berkeley campus. The August 2012 fire there brought a five-hour shelter-in-place order, but it covered Richmond, North Richmond, San Pablo and El Cerrito, not Berkeley. The Air District's advisory for flaring on 31 May 2025 named Richmond, San Pablo, Pinole, Hercules and part of Solano County, again not Berkeley. You may see or smell a flare from north Berkeley; the recorded impacts have generally stayed north of the city.
Is air quality worse in the Berkeley flats than in the hills?
They are different rather than reliably worse. The flats sit alongside Interstate 80, a corridor carrying as many as 270,000 vehicles a day, and near-road pollution falls off sharply within a few blocks, so streets close to the freeway or the Gilman interchange can read higher during peak hours. Elevation adds a second effect: when an inversion forms, the lower city can hold haze while hill streets sit above it. During a wide regional smoke event the whole city tends to read alike. That is why this page shows every sensor rather than one average.
What the AQI numbers mean
| AQI | Category | What it means for you |
|---|---|---|
| 0–50 | Good | Open the windows. Great for outdoor activity. |
| 51–100 | Moderate | Sensitive groups may want to take it slower outside. |
| 101–150 | Unhealthy for Sensitive Groups | Kids, elderly, and respiratory conditions stay closer to home. |
| 151–200 | Unhealthy | Skip outdoor exercise. Close windows. |
| 201–300 | Very Unhealthy | Limit time outside. N95 if you must go. |
| 301+ | Hazardous | Health emergency. Stay inside, run filtration if you have it. |
Canairy lets you tighten these bands if you’re more sensitive than the EPA default, so an alert can fire before the official category changes. How to read the Air Quality Index
Where these readings come from
The AQI at the top of this page is the median of the 5 curated PurpleAir sensors Canairy tracks in and around Berkeley, with outliers set aside so that one sensor brought indoors — or parked beside a barbecue — cannot set the number for a whole city. Every sensor behind it is listed above with its distance and bearing from the city center. There is no black box here.
In the app, a place you save resolves the same way first. When no neighborhood sensor is reporting it falls back to the nearest EPA AirNow monitor, and anything modeled rather than measured is labelled a regional estimate rather than passed off as a sensor reading. How low-cost sensors compare to regulatory monitors
About Canairy
Canairy is free to download. The free plan covers one saved place with live readings, a plain-English verdict, and push alerts when the air crosses a threshold you choose. Paid plans add more places, faster refreshes, and SMS alerts. It is built by two parents in Sonoma County, California, who got tired of guessing whether it was safe to send the kids outside. Why we built it
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Air quality near Berkeley
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