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Anaheim, CA Air Quality Index (AQI) Today

CADominant: O3 LIVE

Readings collected automatically every hour; text written and checked by BreatheCheck Editorial. How this page is made →

Right now: Anaheim is at 46, good.

Is the air safe to breathe in Anaheim today?

46 Good “Unhealthy for everyone” starts at 151 — not 201.

In Anaheim, BreatheCheck reads 46 as Go. The cutoffs: go below 101, keep it short and easy from 101 to 150, move it indoors above 150. These are our own thresholds, drawn on the EPA bands — EPA itself classifies 101–150 as Unhealthy for Sensitive Groups and does not tell you how long to stay out.

Go AQI 0–100

Normal outdoor plans. No change needed.

Short & unloaded AQI 101–150

A 20-minute dog walk, not a 2.5-hour run. Keep it brief and easy.

Don’t go AQI 151+

Move it indoors. Above 200 that becomes everyone, not just sensitive groups.

Go Every combination lands the same way at this reading — a hard hour is no different from an easy twenty minutes. The two dials separate above 80.

All the thresholds people reported, and who reported them
  • 60 Asthmatic runnerone runner’s own 156-run log
  • 75–100 Daycare / schoolparents and staff in one r/toddlers thread, Aug 2025 — not a published rule
  • 100 Parentcommunity-reported, escalating at 150 and 200
  • 110 Runnercommunity-reported

EPA classifies 101–150 as Unhealthy for Sensitive Groups. That is an attributed classification, not a verdict on your lungs specifically.

If you’re staying in, filter the room you’re actually in

A portable HEPA unit or a Corsi-Rosenthal box — one builder put theirs at about $130 for a 12×14 bedroom. We don’t default to a MERV-13 swap in whole-house HVAC: it can restrict airflow, and the safe version needs a static-pressure check first.

See options

O3

5.5 high · modelled

UV hour by hour in Anaheim →

4 of 30 days we have recorded

The record, day by day →

The gap in the hills that sends smog east

Anaheim sits in the middle of a transport chain rather than at either end of it. The city occupies the Orange County plain below the gap where the Santa Ana Canyon cuts east between the Puente and Chino Hills and the Santa Ana Mountains, carrying the river and SR-91 through the barrier. The daytime sea breeze pushes coastal and freeway emissions inland across this plain and through that gap toward Corona, Riverside and San Bernardino. Anaheim is downwind of the coast and upwind of the places that post the basin’s worst ozone numbers.

It is not only a corridor. I-5, SR-57 and SR-91 all cross within a few miles of each other here, so the nitrogen oxides put out on a weekday morning are part of what the afternoon hands to the inland valleys. The bad stretch runs roughly May through October and is worst on hot days with weak onshore flow, when the air crosses the plain slowly enough to keep reacting the whole way.

Autumn runs the sequence backwards. During a Santa Ana the flow comes down out of the interior and out through the same canyon, ending the inland transport for as long as it holds and substituting dust, or in a fire year smoke pushed toward the coast instead of away from it.

Where this number sits

Of the 121 US metros reporting to us right now, Anaheim is number 42 and number 11 of the 12 we track in California. The pollutant driving it today is O3.

Nearby metros we also measure, and what they read at the same hour:

Why a metro a short drive away reads differently →

AirNow’s North Orange CO reporting area, about 2.3 miles from the metro centre.

What has air quality in Anaheim actually been?

Daily maximum, our own readings. 30 days since 2026-08-16; nothing back-filled. Why we keep our own →

4 of the 30 days we have recorded so far went above AQI 100.

Daily maximum AQI recorded for Anaheim, CA
DateDaily max AQIEPA bandHours read
49Good22
47Good22
39Good23
42Good23
54Moderate22
101Unhealthy for Sensitive Groups22
40Good23
24Good23
39Good22
44Good23
41Good23
45Good24
45Good23
47Good23
47Good23
47Good23
119Unhealthy for Sensitive Groups23
97Moderate22
49Good23
80Moderate23
58Moderate23
100Moderate24
126Unhealthy for Sensitive Groups23
90Moderate23
77Moderate23
108Unhealthy for Sensitive Groups23
93Moderate23
84Moderate23
67Moderate26
49Good6 — partial day

Questions about Anaheim

What is the air quality in Anaheim right now?

AQI 46 — Good. That is number 42 of the 121 US metros reporting to us at this hour.

Which monitor does this number come from?

North Orange CO, about 2.3 miles from the metro centre. One instrument reports for the whole metro, so the side farthest from it is the least well described.

How does Anaheim compare with metros nearby?

At this hour: Irvine 46, Long Beach 50, Los Angeles 60, Riverside 73. A gap that size over that distance usually means different terrain, traffic or wind rather than a broken sensor.

Does this include pollen?

No. The AQI covers PM2.5, PM10, ozone, NO₂, SO₂ and CO. A high-pollen day can read clean here and still put someone in bed.

What the number means, band by band → · UV in Anaheim → · Why apps disagree →

Updated