Washburn Fire in Yosemite

Hi PurpleAir Community!

I thought it might be a good idea to create a new category to discuss current air quality and smoke events. I have some thoughts so I’m assuming you might too! Open to your ideas as we discuss and collaborate within this new category.

For example, for the past few days, I’ve been watching PurpleAir sensors around the Yosemite area detect smoke from the Washburn Fire that started on July 7th, 2022. InciWeb regularly publishes updates from Yosemite Fire on the fire details, evacuations, and threats.

As of this morning, July 13th, the Washburn Fire is 3,772 acres but now only 17% contained. This active fire remains a threat to the more than 500 mature giant sequoias of the Mariposa Grove and have so far avoided serious damage from the Washburn Fire. Yosemite Fire reminds us that wildfires play a common role in natural forest management: “Most of these trees are over 2000 years old and have experienced fire many times throughout their lives.”

When looking at the PurpleAir Map, we see elevated air quality readings around the fire, but it is also interesting to note the elevated AQI readings in the South Lake Tahoe area, as well.

This is a good chance to pull up the AirNow Smoke and Fire Map to see the potential transport for this smoke. With winds from the south, the smoke plume is pushed due north, directly into South Lake Tahoe, and has been affecting Tahoe’s air quality since July 8th, 2022.

Any other thoughts on this or stories to share within these areas affected by the Washburn Fire? Looking forward to hearing from you, share and discuss below!

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Interesting analysis, confirming wind direction is key for those outside the immediate area. Parts of the Midwest US often get degraded air from forest fires hundreds of miles to the north in Canada - the smoke is carried by the prevailing winds aloft.


Good idea, Kari. It would be great to have a place where people can talk about how the fires and smoke are impacting them. Being in California, we have been in the middle of several serious wildfires where our air quality has been greatly impacted and the PurpleAir sensors have been very helpful in seeing just how bad the smoke is in different areas. Here is an additional resource focused on California that has smoke outlook/forecast information, links to air quality districts, and other additional information that may be helpful.

California Smoke Information
This site is a voluntary effort by public agencies to coordinate and aggregate information for California communities affected by smoke.

Thanks for sharing! Looks like a great resource for residents in CA.


Yes, a great point, Robert! Not only monitoring the Canadian fires but keeping tabs on the smoke plume transport. I have family in Minnesota that reported hazy skies last fire season. During my visits around that time, the high-level smoke was certainly noticeable. It will be interesting to monitor and report on again this year.

…Anyone else not able to see “Low Cost Sensors” on the AirNow Fire and Smoke Map?

I just noticed that too. I wonder why they took them out.

We are aware and have been working closely with the team to get them back up and running on the AirNow Fire and Smoke map: https://fire.airnow.gov/

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We were in a cabin in the Sierras near Mono Lake on July 5 when an app on my phone went off alerting me that the AQI on my Purple Air Sensor was in the red. Looked at the fire map and found that the Electra Fire had started. We were packed and home 6 hours later to find that the evacuation warning area was a mile from our property and we prepared to evacuate. It didn’t come to that, the winds and CalFire were favorable, but the Electra Fire was in the footprint of the Butte Fire which came up to our back door seven years ago.

Had it not been for the Purple Air sensor on my weather station we never would have known.


Wow, what a close call. Thanks for sharing your story.
Glad you are safe and had the alert enabled. Which app are you using for AQI alerts through your PurpleAir sensor? Airwyn or a different one? Please share!

I use two apps. It was Airwyn that alerted me with the audible tone. It is set (Android) to ask every time to use Location because I don’t want it roaming. I also use AQISpy for location which shows the nearest PrupleAir sensor along with a fire map and weather information.

Cool! I’ll play around with this one! More info here for those who are interested:

Thanks for sharing!

windy.com might be useful for predicting where the smoke is going to go.

its a great tool for visualizing wind, rain and other weather