American Fire Daily Update - August 18

   Prepared by: Mark Fitch and Ryan Bauer

Yesterday, August 17, 2013

The American Fire grew to 12,950 acres yesterday. Smoke from the fire was very visible, again impacting communities throughout El Dorado, Placer, and Nevada, counties this morning. Auburn and Colfax air quality reached the unhealthy range in the morning hours; Foresthill reached hazardous yesterday and are again in the hazardous range this morning. By noon air quality in these areas had returned to the moderate range. Truckee, Reno, Loyalton and Portola were impacted in the evening; all remained in the moderate range.

Sunday, August 18, 2013

Smoke will be wide-spread from north of Grass Valley, south to Placerville and west into the Sacramento Valley.  Foresthill again will see smoke in the hazardous range in the early morning hours. Smoke that settled in Grass Valley and Auburn overnight will lift by late afternoon, but smoky haze will linger throughout the day.  The smoke plume will over pass over Truckee during the day, but will start to settle into the community by late afternoon or early evening. Reno, NV and North Lake Tahoe will also see light smoke light impact in the late afternoon.  South Lake Tahoe will remain relatively clear with just some light haze.  Air quality in the Sacramento Valley will see light impacts; AQI levels should not exceed the moderate range. 

Monday, August 19, 2013

Smoke will return to the Forest Hill, Auburn, Grass Valley, and Placerville area with onset of the downslope winds. Impacts will be highest in the early morning, improving by late afternoon, with smoke visible all day.  Smoke plume will pass over Truckee during the day collapsing in the evening, elevating PM2.5 levels.  Smoke that settled during the night in the Sacramento valley will lift by late morning, early afternoon; however, a light smoke haze may be visible all day.

Long-range Outlook

The cutoff low will park itself off the Monterey coast. Thunderstorms will develop north of the low bringing more lightning and possibly some rain by mid-week.

Site	24-hour Average PM2.5 (μg/mᵌ)	3-hour Max PM2.5 (μg/mᵌ)	Level of Health Concern	Meaning	Actions to Protect Yourself
Quincy Roseville	10 10	21 22	Good	Air quality is satisfactory and poses little or no health risk	None
Reno Truckee Lincoln Portola Loyalton	30 32 23 21 19	45 71 57 35 57	Moderate	Air quality is acceptable for most. There may be moderate health concern for a small number of sensitive people.	Unusually sensitive people should consider reducing prolonged or heavy outdoor exertion.
Grass Valley	22	79	Unhealthy for Sensitive Groups	Members of sensitive groups may experience health effects.  The general public is not likely to be affected.	People with heart or lung disease, children and older adults should reduce prolonged or heavy outdoor exertion.  Everyone else should limit prolonged or heavy exertion.
Colfax Auburn	54 61	152 159	Unhealthy	Everyone may begin to experience more serious health effects.	The following groups should avoid all physical outdoor activity: People with heart or lung disease, children and older adults.  Everyone else should avoid prolonged or heavy exertion.
			Very Unhealthy	Significant aggravation of heart and lung disease. Everyone may experience more serious health effects	Everyone should avoid any outdoor exertion; people with respiratory or heart disease, the elderly and children should remain indoors.
Foresthill	233	658	Hazardous	Serious aggravation of heart and lung disease. Everyone may begin to experience more serious health effects.	People with heart or lung disease, children and older adults should avoid all physical outdoor activity. Everyone else should avoid prolonged or heavy exertion