Air quality in the unhealthy range in South Lake Tahoe

The air quality in South Lake Tahoe dipped into the "unhealthy" range on Sunday, prompting some to wear protective mouth masks.

From 8 a.m. to 9 a.m., air quality hit the worst levels of the day with a registered 134.5 Micrograms/Cubic Meter (ug/m3) according to the California Air Quality and Meteorological Information System (AQMIS).

This calculates to a 192 AQI which is in the "unhealthy" range. By 3 p.m. this lowered to 153 AQI, which is still in the same range, but South Lake Tahoe was back down into the "unhealthy for sensitive group" range by 5 p.m. with an AQI of

Both of these measurements are a result of testing for particulates under 2.5 microns.

The fire causing the unhealthy smoke is still ranging near Jackson, with another powerful blaze to the west exploding in just one day to 50,000 acres burned in Lake County. The Butte Fire is now 20% contained after burning 65,215 acres.

As of Sunday afternoon, 81 homes had burned in the Butte Fire along with 51 outbuildings.

Some residents are being allowed back into their homes. Phase 1 is letting people on the following streets back:

All residences on East Clinton Road, to Clinton Road
Residences on Irish Town Road and Clinton Road to East Clinton Road
All residences on Mount Zion/Lookout Road area
All residences on Tabeau Road from Hwy 88 to South of Arrowhead
All residences on Clinton Road from Amador Lane/Tabeau Road to East/West Clinton split.

All other areas are still evacuated.

In the Valley Fire in Lake County is threatening the critical communications infrastructure in the Geysers area, as well as, threatening the Adalin Power Plant (Cal Pine). There have been an unconfirmed number of structures destroyed. Over 5,000 are without power.