Air Quality in San Juan, Washington

Q: What is the air quality in San Juan, Washington?

Based on EPA data, San Juan has a median AQI of 21 (Good). The primary pollutant is PM2.5.

Q: Is San Juan a good place to live for air quality?

San Juan has a 10-year average median AQI of 21 with 111 good air quality days in 2019.

Median AQI (2019)

Max AQI (2019)

↓ improving

10-Year Trend

PM2.5

Primary Pollutant

111

Good Days (2019)

Monitoring Stations

AQI Trend (Median)

Air Quality Days by Category

Annual Summary

Year	Median AQI	Max AQI	Good Days	Moderate Days	Unhealthy Days	Ozone Days	PM2.5 Days
2019	21	52	111	1	0	0	112

Recent Daily AQI

Date	AQI	Category	Primary Pollutant
May 29, 2019	26	Good	PM2.5
May 28, 2019	45	Good	PM2.5
May 27, 2019	40	Good	PM2.5
May 26, 2019	23	Good	PM2.5
May 25, 2019	24	Good	PM2.5
May 24, 2019	31	Good	PM2.5
May 23, 2019	32	Good	PM2.5
May 22, 2019	21	Good	PM2.5
May 21, 2019	19	Good	PM2.5
May 20, 2019	18	Good	PM2.5
May 19, 2019	16	Good	PM2.5
May 18, 2019	18	Good	PM2.5
May 17, 2019	13	Good	PM2.5
May 16, 2019	19	Good	PM2.5
May 15, 2019	17	Good	PM2.5
May 14, 2019	24	Good	PM2.5
May 13, 2019	27	Good	PM2.5
May 12, 2019	25	Good	PM2.5
May 11, 2019	23	Good	PM2.5
May 10, 2019	25	Good	PM2.5
May 9, 2019	18	Good	PM2.5
May 8, 2019	22	Good	PM2.5
May 7, 2019	16	Good	PM2.5
May 6, 2019	18	Good	PM2.5
May 5, 2019	17	Good	PM2.5
May 4, 2019	18	Good	PM2.5
May 3, 2019	18	Good	PM2.5
May 2, 2019	19	Good	PM2.5
May 1, 2019	25	Good	PM2.5
Apr 30, 2019	17	Good	PM2.5
Apr 29, 2019	17	Good	PM2.5
Apr 28, 2019	18	Good	PM2.5
Apr 27, 2019	14	Good	PM2.5
Apr 26, 2019	24	Good	PM2.5
Apr 25, 2019	22	Good	PM2.5
Apr 24, 2019	22	Good	PM2.5
Apr 23, 2019	22	Good	PM2.5
Apr 19, 2019	16	Good	PM2.5
Apr 18, 2019	20	Good	PM2.5
Apr 17, 2019	11	Good	PM2.5
Apr 16, 2019	27	Good	PM2.5
Apr 15, 2019	15	Good	PM2.5
Apr 14, 2019	13	Good	PM2.5
Apr 13, 2019	14	Good	PM2.5
Apr 12, 2019	10	Good	PM2.5
Apr 11, 2019	21	Good	PM2.5
Apr 10, 2019	14	Good	PM2.5
Apr 9, 2019	21	Good	PM2.5
Apr 8, 2019	21	Good	PM2.5
Apr 7, 2019	15	Good	PM2.5
Apr 6, 2019	16	Good	PM2.5
Apr 5, 2019	13	Good	PM2.5
Apr 4, 2019	22	Good	PM2.5
Apr 3, 2019	20	Good	PM2.5
Apr 2, 2019	21	Good	PM2.5
Apr 1, 2019	21	Good	PM2.5
Mar 31, 2019	30	Good	PM2.5
Mar 30, 2019	27	Good	PM2.5
Mar 29, 2019	23	Good	PM2.5
Mar 28, 2019	14	Good	PM2.5
Mar 22, 2019	21	Good	PM2.5
Mar 21, 2019	26	Good	PM2.5
Mar 20, 2019	25	Good	PM2.5
Mar 19, 2019	21	Good	PM2.5
Mar 18, 2019	20	Good	PM2.5
Mar 17, 2019	25	Good	PM2.5
Mar 16, 2019	26	Good	PM2.5
Mar 15, 2019	34	Good	PM2.5
Mar 14, 2019	21	Good	PM2.5
Mar 13, 2019	23	Good	PM2.5
Mar 12, 2019	19	Good	PM2.5
Mar 11, 2019	27	Good	PM2.5
Mar 10, 2019	39	Good	PM2.5
Mar 9, 2019	31	Good	PM2.5
Mar 8, 2019	21	Good	PM2.5
Mar 7, 2019	21	Good	PM2.5
Mar 6, 2019	24	Good	PM2.5
Mar 5, 2019	21	Good	PM2.5
Mar 4, 2019	21	Good	PM2.5
Mar 3, 2019	15	Good	PM2.5
Mar 2, 2019	18	Good	PM2.5
Mar 1, 2019	30	Good	PM2.5
Feb 28, 2019	22	Good	PM2.5
Feb 27, 2019	14	Good	PM2.5
Feb 26, 2019	14	Good	PM2.5
Feb 25, 2019	11	Good	PM2.5
Feb 24, 2019	9	Good	PM2.5
Feb 23, 2019	19	Good	PM2.5
Feb 22, 2019	26	Good	PM2.5
Feb 21, 2019	26	Good	PM2.5

Monitoring Stations

Mobile FDH San Juan

Friday Harbor

Est. 2019-01-07

48.5355, -123.0197

Frequently Asked Questions

What is the air quality in San Juan, Washington?

Based on EPA data from 2019, San Juan has a median Air Quality Index (AQI) of 21, which is classified as "Good." The primary pollutant is PM2.5. Over the past 10 years, air quality has been improving.

Is San Juan a good place to live for air quality?

San Juan has a 10-year average median AQI of 21. In 2019, there were 111 days with "Good" air quality and 0 days with unhealthy conditions. No special precautions are needed for most people.

What pollutants affect San Juan the most?

The primary pollutant driving the AQI in San Juan is PM2.5. This is monitored by 1 active EPA stations in the county. Other pollutants tracked include ozone, PM10, nitrogen dioxide, sulfur dioxide, and carbon monoxide.

How many air quality monitoring stations are in San Juan?

There are 1 active EPA monitoring stations in San Juan, Washington. These stations continuously measure pollutant levels and contribute to the daily AQI calculations.