[UPDATE 10:28 a.m.] Air Quality at Unhealthy Levels for Much of the Emerald Counties

Air quality map

Air quality map from the EPA.

Air quality for much of the Emerald Counties is now in the unhealthy level due to smoke mostly from the Camp Fire in Butte County which has consumed around 135,000 acres.

Although at an air quality index of 151, Eureka is on the low end (an index rating of 150 to 101 would be only unhealthy only for sensitive groups), this is still a serious level indicating that everyone may begin to have their health affected and those in sensitive groups may begin to have serious side effects.

Chart showing air qualityThe EPA recommends that people avoid prolonged or heavy exertion outside when the air quality is rated as unhealthy.

UPDATE 10:28 a.m.: The local North Coast Unified Air Quality Management District (NCUAQMD) and partners reports a slightly lower level of concern;

Humboldt, Del Norte County & Trinity County
Increasing smoke impacts from the Camp Fire have been present in coastal areas of Humboldt and Del Norte County. Overall smoke impacts are forecast to be “Moderate” to “Unhealthy for Sensitive Groups” with periods of “Unhealthy” depending on weather and location. Weather forecasts indicate light northerly wind late this evening which should help bring some improvement in conditions.
It is anticipated that smoke will continue to linger in the area until conditions change. Smoke levels will vary depending on weather conditions and fire activity. As is typical for this time of year, overnight inversions will limit smoke dispersion until the day starts to warm up.
• Coastal Areas (Crescent City to Shelter Cove) – overall “Moderate” to “Unhealthy for Sensitive Groups” with brief periods of “Unhealthy” depending on conditions
• Southern Humboldt – “Moderate” to “Unhealthy for Sensitive Groups” with periods of “Unhealthy” depending on conditions
• Inland Humboldt and Del Norte County – “Moderate” to “Unhealthy for Sensitive Groups”
• Trinity County – “Moderate” with periods of “Unhealthy for Sensitive Groups”
Particulate Matter (PM2.5) monitors are presently in Crescent City, Gasquet, Eureka, and Weaverville. Updates will be provided as conditions change. For 24-hour Air Quality Advisory Information, call toll-free at 1-866-BURN-DAY (1-866-287-6329).
Fire information can be found at http://inciweb.nwcg.gov/ or at www.calfire.ca.gov. Current weather information can be found at www.wrh.noaa.gov.



  • Thanks for posting, Kym. People can also check at http://www.airnow.gov and entering their zipcode. This is an EPA site that updates hourly.

  • According to a formula created by Berkeley Earth, an Air Quality Index of 150 is equal to smoking about seven cigarettes a day.


  • The Hermit of Grizzly Mountain

    I’ve been noticing discrepancies between airnow.gov and purpleair.com, which supposedly get their data from the same source(s). Not sure why, or which is more accurate.

    • They don’t get their data from the same sources.

      AirNow is based on the very small number of regulatory monitors in the region and is updated hourly — presumably these would be NCUAQMD’s monitors. The NCUAQMD only has two regulatory monitors for all of Humboldt County, and both are in Eureka. It’s ludicrous for them to be sending out air quality info for the entire county based on that.

      The PurpleAir sensors are privately owned “citizen science” monitors that give readings in real time. They are not regulatory monitors, but PurpleAir monitors have been tested independently and found to correlate well with regulatory monitors in the size range that matters most — PM2.5. A growing number of agencies, as well as private people, have been setting them up. The National Weather Service’s Bay Area branch, for example, tweeted screenshots the other day from the PurpleAir map and wrote that the info from PurpleAir was closely tracking the readings from the regulatory monitors down there. One of the advantages of PurpleAir is the sensors are located in residential and commercial areas where people are actually breathing — rather than on an isolated hilltop somewhere.

      You could join the PurpleAir network yourself if you wanted to — purchasing info is available on the PurpleAir website. All you need is access to an outdoor electrical outlet. (I was the first person in this area to set up a PA sensor. I hope more people will join the network — the more sensors we have, the more information we get about our local air quality.)

  • this smoke is toxic. it is primarily rubber, foam, glues, epoxies, household haz mats like pesticides, oil, etc, vinyl, and other building materials.

Leave a Reply

Your email address will not be published. Required fields are marked *