Air Quality in Oceanside, California — Live
Live readings from PurpleAir sensors across Oceanside — with free alerts the moment the air turns.
AQI 59 from 5 PurpleAir sensors · Trending up · data from PurpleAir
As of , the air quality in Oceanside, California is AQI 59 — Moderate and rising — with PM2.5 at 13.2 µg/m³, the median of 5 live PurpleAir sensors reading 51 to 62. Canairy's verdict: Mostly clear.
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 Oceanside: 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 Oceanside and Carlsbad, Vista, San Marcos, Camp Pendleton, Bonsall, Fallbrook. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Oceanside
The sensors Canairy reads in Oceanside agree right now — all 5 sit in the Moderate band, a 11-point spread — so the city-wide number is a fair description of the whole area today.
| From city center | AQI | Category |
|---|---|---|
| 2.2 mi ESE | 61 | Moderate |
| 2.6 mi NE | 56 | Moderate |
| 3.4 mi SE | 51 | Moderate |
| 3.9 mi S | 62 | Moderate |
| 5.0 mi SE | 59 | Moderate |
Oceanside is the northernmost coastal city in San Diego County — heading north on Interstate 5, the last one before Orange County. It covers about 42 square miles, had 174,068 residents at the 2020 census, and has the San Luis Rey River running through it to the sea and a small-craft harbour at the north end of the beach. The climate is mild semi-arid, in the city's own description significantly tempered by maritime winds and the cool currents off the shoreline, with average highs between 64 and 77°F. Immediately north is Marine Corps Base Camp Pendleton: over 125,000 acres of mostly undeveloped land with 17 miles of coastline. Most of the year that combination — steady onshore air, no heavy industry, ocean rather than a valley wall on one side — gives Oceanside genuinely good air. The exceptions are worth knowing about, and they nearly all involve fire.
What Canairy does for Oceanside
A clear verdict
Not just a number — a plain-English call for Oceanside: 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 Oceanside or across the country, on one screen.
The base to the north is open country, and open country burns
Wildfire is not uncommon on Camp Pendleton's undeveloped land, and because the base sits directly upwind of Oceanside on many days, a fire there is Oceanside's fire whether or not a single flame crosses the boundary. The November Fire is a fair example. It started around 10 a.m. on Wednesday 10 June 2026 in the southern part of the base, a few miles northeast of Interstate 5, and by 2:30 that afternoon it had reached 560 acres at zero containment. The San Diego County Air Pollution Control District issued a smoke advisory naming Camp Pendleton, Oceanside, Bonsall and Fallbrook, warning that air quality in heavily impacted areas was expected to range from unhealthy for sensitive groups to unhealthy for all individuals, and advising residents to limit outdoor activity and stay indoors where possible, "especially those with respiratory or heart disease, children and the elderly."
Less than a month later the Pipeline Fire burned on the same base, reaching 1,065 acres and prompting another district smoke advisory — that one covering Alpine, Fallbrook, Pala, Ramona and Valley Center rather than the coast, because the wind was different. Neither fire was a catastrophe. Both were ordinary base fires that put smoke over North County for a day or two, and two of them landed inside a single month in the summer of 2026. That is the shape of the risk here: not many disasters, but short, fast-moving smoke events where the advisory and the smell arrive at roughly the same time.
The larger fires have come from inland, on a Santa Ana wind
In May 2014 a cluster of fires burned across North County at once. The Las Pulgas Fire began at 2:45 p.m. on 15 May near Interstate 5 at Las Pulgas Road on Camp Pendleton and became the largest of the outbreak at 14,416 acres before it was contained on 21 May. The Tomahawk Fire, which had started the day before, burned 5,367 acres, and the San Mateo Fire near Camp Talega added another 1,457. In the same week the Poinsettia Fire destroyed 28 structures in Carlsbad, just down the coast, with damage put at $22.5 million.
In December 2017 the Lilac Fire started at 11:15 a.m. on 7 December near Old Highway 395 and Dulin Road in Bonsall, where State Route 76 meets Interstate 15. Winds pushed it west toward Oceanside and Vista, and there was real concern it could run all the way to the Pacific near Camp Pendleton. It burned 4,100 acres, destroyed 157 structures and damaged 64; roughly 10,000 residents were evacuated and more than 100,000 were advised or ordered to leave. The pattern in both cases is the same one that catches people out on the coast: a Santa Ana wind blows from the inland deserts toward the ocean, which is exactly the direction that puts inland smoke over a beach town.
The ocean does most of the work the rest of the year
San Diego County as a whole is listed by EPA as nonattainment for the 2015 eight-hour ozone standard at a Severe-15 classification, but that burden is not spread evenly. Ozone builds inland on hot still afternoons, downwind of where the emissions were made. The air district's nearest regulatory station to Oceanside is on Camp Pendleton, measuring ozone, nitrogen dioxide, PM2.5 and PM10; on 27 July 2026 its eight-hour ozone average was 0.036 ppm, against 0.053 ppm at Alpine in the backcountry. Coastal air here is usually the good end of the county's range.
The local sources that remain are ordinary ones. Interstate 5 runs the length of the city and then follows the coastline for another 18 miles north through Camp Pendleton and San Onofre; State Routes 76 and 78 meet it here. None of that will ruin a week, but it can make one block read noticeably worse than the city average on a still morning — which is the argument for watching the sensor nearest you rather than one number labelled "Oceanside."
Oceanside air quality FAQ
What is the air quality in Oceanside right now?
As of September 11, 2026 at 8:19 AM PDT, the air quality in Oceanside, California is AQI 59 — Moderate — with PM2.5 at 13.2 µg/m³, the median of 5 live PurpleAir sensors. Sensitive groups may want to take it slower outside.
Why is there smoke in Oceanside today?
Very often a brush fire on Camp Pendleton, immediately north of the city. On 10 June 2026 the November Fire reached 560 acres in the southern part of the base and the San Diego County Air Pollution Control District issued a smoke advisory naming Camp Pendleton, Oceanside, Bonsall and Fallbrook, warning air quality could range from unhealthy for sensitive groups to unhealthy for everyone. The other common cause is an inland fire on a Santa Ana wind, which blows from the deserts toward the ocean — the December 2017 Lilac Fire started in Bonsall and was driven west toward Oceanside and Vista.
Do fires on Camp Pendleton affect Oceanside's air?
Yes, and regularly enough to plan for. Wildfire is not uncommon on the base's 125,000 acres of undeveloped land, and the county air district names Oceanside directly in its smoke advisories when a fire burns on the southern side. In the summer of 2026 alone, the November Fire in June and the Pipeline Fire in July — the latter reaching 1,065 acres — both prompted district smoke advisories in North County. These events tend to last a day or two rather than a week, but they escalate fast.
Is Oceanside's air quality good?
Most of the time, yes. The onshore marine flow that tempers the climate also keeps pollution moving, and the coastal monitors read at the cleaner end of San Diego County's range — on 27 July 2026 the eight-hour ozone average at the Camp Pendleton station was 0.036 ppm against 0.053 ppm inland at Alpine. The honest caveat is that Oceanside's bad days are sudden rather than seasonal: a brush fire on the base or a Santa Ana pushing inland smoke to the coast can take the air from clean to unhealthy within an afternoon.
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 Oceanside, 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 Oceanside
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