San Mateo air quality · California, United States
Deep breaths feel amazing when the air is this clean
US AQI 33 (Good) in San Mateo, from 1 AirNow monitoring station. Main pollutant: PM2.5.
Updated
Pollutants in San Mateo
- PM2.533AQI
- NO₂2AQI
- Ozone31AQI
US values are per-pollutant AQI from the highest-reading monitor near San Mateo (Oakland).
Is it safe outside in San Mateo right now?
Air quality is satisfactory and poses little or no risk.
Walking and commuting
Go aheadEnjoy it.
Running and jogging
Go aheadA great time to run outdoors.
Cycling
Go aheadRide freely.
Children playing outside
Go aheadNo limits.
Older adults and heart or lung conditions
Go aheadNo limits.
Open windows
Go aheadAir out your home.
Mask outdoors
Not neededNot needed.
Air purifier indoors
Not neededNot needed.
Based on the US EPA Air Quality Guide, applied to the current US AQI category. If you have symptoms, follow your doctor's advice.
What US AQI 0–50 means for your health →
San Mateo air quality history
Daily average, 36 days- 44average daily US AQI over 36 days
- 60worst day, 3 October
- 21cleanest day, 22 September
- 0days at Unhealthy or worse
The last 7 days averaged 49, about the same as the week before (46). 24 of the last 36 days were Good.
Weather in San Mateo
No active National Weather Service alerts for San Mateo.
| Day | Forecast | High | Low | Rain |
|---|---|---|---|---|
| Mon 19 | Partly Sunny | 66°F | 52°F | 8% |
| Tue 20 | Mostly Cloudy | 70°F | 54°F | 74% |
| Wed 21 | Rain Showers Likely | 70°F | 54°F | 74% |
| Thu 22 | Chance Rain Showers | 68°F | 54°F | 25% |
| Fri 23 | Sunny | 72°F | 52°F | 1% |
| Sat 24 | Sunny | 72°F | 54°F | 21% |
| Sun 25 | Slight Chance Light Rain | 72°F | 52°F | 21% |
National Weather Service forecast. All US weather alerts →
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San Mateo air quality: common questions
What is the AQI in San Mateo right now?
The US AQI in San Mateo is 33 (Good). The main pollutant is PM2.5.
Is it safe to go outside in San Mateo today?
A great time to be outside. Air quality is satisfactory and poses little or no risk. For runners: A great time to run outdoors.
How has air quality in San Mateo been recently?
Over the last 36 days with data, San Mateo averaged US AQI 44. The worst day was 3 October at 60; the cleanest was 22 September at 21. 0 days were at Unhealthy or worse.
Where does San Mateo's air quality data come from?
From US EPA AirNow, using 1 monitoring station in and around the city. Good Air does not estimate or adjust these readings.
Source: US EPA AirNow. Readings are published by the monitoring agency and may be revised.