Air Quality Update--September 6, 2013
Incident: Rim Fire Wildfire
Yesterday September 5 2013
Over the past two days the Rim Fire has grown approximately 9 000 acres the majority of which occurred yesterday. It is currently 246 350 acres. Smoke under the inversion cleared by around noon in most areas. Transport winds had a slightly more westerly component so smoke returned to communities northeast of the fire including Pinecrest Bear Valley Markleeville and Minden but remained just south of Carson City and the Lake Tahoe Basin. The Yosemite and San Joaquin Valleys were not impacted by smoke from the Rim Fire.
Friday September 6 2013
Conditions this morning are a little better than yesterday in many areas. The heaviest morning smoke impacts are in communities to the northeast and in the immediate fire area such as Pinecrest Bear Valley Markleeville and Minden. Morning smoke was not as heavy in Carson City South Lake Tahoe Tuolumne City and Sonora. This morning’s inversion should break a little before noon. All areas should see their best air quality in the afternoon. Daytime transport winds will remain southwesterly keeping smoke out of the Yosemite Valley El Portal and the San Joaquin Valley. Nighttime impacts similar to yesterday are likely for Carson City and Minden continuing into Friday morning.
Saturday September 7 2013
The weather pattern is changing. Transport winds begin to weaken some and become more west-southwesterly. The morning inversion is still forecast to be quite strong and likely to persist until around noon. Morning smoke impacts in communities within the immediate fire area and south and west of the fire in Mariposa La Grange Greeley Hill Columbia and Sonora are likely. Pinecrest Bear Valley Markleeville and Minden will still see the heaviest impacts. All areas should clear for a few hours in the afternoon. The Yosemite Valley should remain in the good range although Tuolumne Meadows may begin to see some impacts as winds become more westerly.
Long term Outlook
Sunday morning smoke impacts are predicted to extend further into the central valley mainly to the west and northwest of the fire area but impacts are possible further south in the northern San Joaquin Valley as well. Daytime transport winds are forecast to become west to northwest with the possibility of sending smoke from the Rim fire into the Yosemite Region. Widespread light smoke is predicted to cover much of the north state as the region sees a general decrease in smoke dispersion and transport going into next week.