Updated Aug 2, 2022 (final update)
Short version: the fires in the Yosemite region are all doing very well, have remained within the control lines for at least a few days now and are producing little smoke. Air quality is very good and everything in the park that was closed by the fire has reopened. No sequoia trees were lost and the Mariposa Grove, including the grove shuttle, has reopened. The one exception is the Washburn Trail, which is where the fire started, presumably because of hazardous trees.
We have long since resumed our normal activities. Tom went for a nice 9-mile run on July 30 with great views and we have resumed climbing and running and hiking and are taking a few days off next week to go backpacking. Conditions are currently excellent.
The Washburn Fire started July 7 and currently stands at 4,886 acres. It has seen no growth in four days and has only grown 30 acres in the last 10 or 11 days. It is 97% contained and the remaining 3% is burning in rocky terrain at low intensity within the control lines. Fire crews have almost fully demobilized from that fire.
The official source of information, as for all wildfires on federal lands, is the Inciweb page for the Washburn Fire. As the Washburn crews demobilize, there is no longer a daily briefing because for all intents and purposes, this fire is done. You can view the actual operations briefing for the fire crews on the YosemiteFire Facebook page.
The Oak Fire started July 22 and currently 19,244 acres, which is unchanged over the last few days. Almost all residential areas have been repopulated, with a couple of small exceptions as fire crews continue to work on a small section on the NE flank and as the power company crews try to secure the electrical system in communities that were hit by the fire. The NE flank is still not marked as controlled, but according to the recent morning briefings, they have made a lot of progress and are in a mop up mode as they strengthen and deepen those lines until they feel confident to declare it contained.
The best source of information on the Oak Fire is on the CalFire Oak Fire Incident page. You can view the daily operations briefing on the CalFireMMU Facebook page. These briefings are usually under three minutes and give a great overview of what’s happening on the fire.
Western Fire Chiefs Association fire map. Super helpful map that shows very clearly growth from the current day, the previous day and prior to that. You can also click on the fire and it will give you growth in the last 24 hours. This is a national map that updates in real time as new data is released.
Smoke impacts tend to be most intense during periods of fast fire growth and these fires have been no exception. During the fast-growth phase of both fires, we had really really bad air. After a respite and some great conditions as they got a handle on the Washburn, the Oak put an end to that.
Air quality in the last several days has been good to excellent. We have generally been within the EPA “Good” range, which means better than most days in Los Angeles. If we are going to have bad air, it will not be from these two fires.
Air quality can vary a lot with conditions (wind direction, fire intensity, inversion layers). Air quality forecasts tend to be rough estimates and much less accurate than weather forecasts.
- Real time air quality from AirNow.gov (search on Wawona, CA, to zoom in on the right spot). This map shows both regulatory-grade and low-cost sensors. The regulatory grade are more accurate. The low-cost sensors are mostly Purple Air, which tend to be way off without the woodsmoke correction factor. It is better to view those on Purple Air and apply the proper correction.
- Purple Air. These are cheap sensors that can be way off, but there are more of them in more places, so they help round out the picture. If you compare the regulatory-grade sensors in Wawona and Yosemite Valley to Purple Air sensors right near them, you can see a major variance. Sometimes Purple Air is very low. Sometimes it is very high.
- Smoke Forecast. From Hanford weather station. Take with a grain of salt, but these forecasts seem to be getting better each year.