Tuesday, September 3, 2013

9/3/2013 Rim Fire Extended Air Quality Report

Rim Fire, Air Quality Resource Advisor Report                               Tuesday, September 3, 2013
 Prepared by: Ron Sherron, Leland Tarnay, Sharon Grant, and Ryan Bauer
Key Points:
  • Fire has burned 235,841 acres.  7,171 acres of growth during the last operational period.
  • Weather conditions will be similar to yesterday, although slightly drier.  Expect unstable conditions with a chance of light showers.  There is a possiblity for thunderstorms in the area that could cause gusty outflow winds over the fire.  Light southeasterly winds early will become south before turning south-southwesterly with gusts up to 20 MPH possible on the ridgetops.
  • Crews will continue direct attack on the eastern portion of the fire in Division N. Divisions A,B,D, and E will finish mop-up and patrol of the area. The firing operation in Division F has been slowed by higher humidities, but they expect to make good progress today, using aerial ignitions to deepen their burnout. Efforts to contain the spot fire in Division S continue; crews made good progress but could not complete a fireline under the spot fire because of heavy fuels and steep terrain (Figure 1).
  • Team Transition will begin today with incoming team members shadowing their counterparts.
Figure 1 Rim fire operations map for 9/3/2013 with MODIS satellite heat detections from 07:30 today (orange dots represent activity within past 12-24 hrs, red dots represent activity within past 6-12 hours) showing location of the spot fire in Division S, and planned aerial burnout ignition in Division F.

Figure 2 Rim fire infrared perimeter from 23:00 9/2/2013 with visible satellite image from 08:30, 9/3/2013 showing outline of visible smoke.

Satellite imagery from this morning shows the main body of smoke from the Rim Fire extending north over Pinecrest, Markleeville, the Lake Tahoe Basin, Minden, Carson City, and Reno/Sparks (Figure 2). Air quality monitors in those locations report impacts in the very unhealthy range in Pinecrest, decreasing to unhealthy in Markleeville, and unhealthy for sensitive groups in Minden, Carson City. Smoke just skirts the Lake Tahoe Basin and Reno/Sparks areas with slight impacts in the moderate range (Figure 4). BlueSky model predictions were a little bit off on this, not anticipating a more southerly influence in transport winds just east of the Sierra crest (Figure 3). Yesterday’s smoke impacts in Minden an Carson City were forecast, but for slightly lower impacts than those experienced in those locations.

Also shown in figure 2 is an area of smoke that settled into the central valley overnight due to the slightly stronger inversion. Impacts from this so far have only occurred in Tuolumne City.
Figure 3 visible satellite image from 18:00 9/2/2013 and 2km BlueSky particle model prediction for the same hour, showing the difference in predicted and actual smoke plume travel east of the Sierra crest.

Figure 4 3-hour average fine particulate (PM 2.5) concentration at eight (8) monitoring locations adjacent to the Rim fire with associated Air Quality Index (AQI) health hazard ranges and adjectives. All data are preliminary and have not undergone quality assurance review.

Air Quality in the Yosemite region remains in the good range (Figure 5). Southwest winds expected to remain dominant over the next several days should keep air quality in the Yosemite region good through Friday.

Figure 5 3-hour average fine particulate (PM 2.5) concentration in the Yosemite region with associated AQI ranges and adjectives. All data are preliminary and have not undergone quality assurance review.

Figure 6 air quality monitoring sites in the Rim Fire area with Rim fire infrared perimeter from 20:18, 9/1/2013.

Table 1 selected air quality monitor data and corresponding AQI rating, meanings, and recommendations with forecast levels for today. Data are preliminary and have not undergone quality assurance review.
Follow the links in the following table to view real-time air quality monitoring data for each site.

24-hour Avg PM2.5
3-hour Max PM2.5
Level of Health Concern


Actions to Protect Yourself
For Tues.
Sept. 3, 2013
Yesterday, Sept. 2, 2013
La Grange
Greeley Hill
El Portal
Yosemite Vly
Air quality is satisfactory and poses little or no health risk
La Grange
Yosemite Vly.
Tuol. Mdws



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.

S. Lk. Tahoe Tuol. City
Carson City
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.
S. Lk. Tahoe
Tuol. City

Bear Valley



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.
Bear Valley

Drew Mdw ICP
Very Unhealthy
Triggers a health alert, meaning 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.

Air Quality Index (AQI) ratings are derived based on the recommendations found in Wildfire Smoke: A Guide for Public Health Officials.

Tuesday, September 3, 2013
Smoke again had the heaviest impacts to communities to the northeast and in the immediate fire area such as Pinecrest, Bear Valley, Tuolumne City, Markleeville, South Lake Tahoe, Carson City, and Minden. Morning inversions were a little stronger but started to break around 10:00. Atmospheric conditions will be very similar to yesterday. All areas should see their best air quality in the afternoon except perhaps Pinecrest. Daytime transport winds will remain southwesterly, reducing impacts to the Yosemite Valley, El Portal, and the San Joaquin Valley. East of the Sierra crest smoke transport will likely see the same southerly influence in the evening hours as yesterday, causing impacts to Gardnerville, Minden, and Carson City late in the night and into the following morning, similar to what is shown in figure 3.
Wednesday, September 4, 2013
Smoke impacts will be similar to today’s. Morning impacts will be highest north of the fire area, with smoke likely in Pinecrest, Bear Valley, Tuolumne City, Markleeville, South Lake Tahoe, Carson City, and Minden (Figure 7). Inversions will be a bit stronger and could persist a few hours later before breaking. Southwest winds will continue to clean out smoke basins by early afternoon and should keep areas south and southwest of the fire mostly smoke free. Carson City and Gardnerville/Minden may again see similar impacts in the evening with more southerly transport flows (not shown in the BlueSky models) affecting the smoke east of the Sierra crest (figure 8).

Figure 7 2 km BlueSky particle model prediction for 07:00 9/3/2013.

Figure 8 2 km BlueSky particle model prediction for 16:00 9/4/2013.
Thursday, September 5, 2013
Smoke impacts continue to follow the pattern of the past two days. There is some hint that early morning impacts could extend further south and west of the fire area than the two previous days, possibly impacting La Grange, Sonora, and Columbia (figure 9). Inversions will be the strongest seen this week. Southwest winds will continue their dominance, cleaning smoke out of the west slopes of the Sierras by early afternoon. The BlueSky model suggests a slightly more northerly path for the plume in the afternoon (Figure 10).
Figure 9 2 km BlueSky particle model prediction for 07:00 9/5/2013.

Figure 10 2 km BlueSky particle model prediction for 16:00 9/5/2013.
Long-range outlook
Southwest transport winds will dominate through Friday. This should keep air quality in the Yosemite Valley and areas south of the fire in the good to moderate range. Areas north and northeast of the fire, including the Lake Tahoe Basin, and Washoe and Carson valleys will see similar impacts through the week. Communities within the immediate fire area will continue to see intense morning smoke with afternoon clearing. By this weekend winds are predicted to shift to a light northwest flow for Saturday into early next week. This could return smoke to the Yosemite Valley depending on fire activity on the Rim incident.                                                                      


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