08/18/2016 Idaho DEQ Smoke Forecast

Updated 10am MDT Thursday, August 18, 2016

Valid through Noon MDT Friday, August 19, 2016

Smoke Outlook

Air quality is forecast to continue to remain in the Good to Moderate air quality category across the state today with higher readings across Boise County, Blaine County, and Camas County due to the proximity and drainage of the Pioneer Fire.  Current elevated DEQ monitors include Nampa, Boise, Garden Valley, Salmon, and Ketchum which are all reading in the Moderate category.  Idaho City is currently reading in the Unhealthy for Sensitive Groups Category.

                                                  

A minor disturbance will pass through the upper level ridge today, providing a chance for showers along the extreme ID/UT border and across parts of the Central Idaho Mountains this afternoon.   A cold front passing through northern Idaho will allow for a slight chance of isolated thunderstorms this afternoon across the northern Panhandle.  Due to the ridge pattern, inversions will be quite slow to mix out because of warm mid-layers.  Surface wind speeds will be in the 8-12 mph range across the southwestern portion of the state with 5-10 mph speeds within the Upper Snake River Plain this afternoon.  The wind direction will be from the west-northwest across all of southern Idaho with northeast winds across the Panhandle at 10-15 mph.  The Clearwater, Palouse, and Camas and Weippe Prairies will see winds from the northwest at 5-10 mph.  The atmosphere will become unstable to between 4,000-10,000 feet AGL late this afternoon with a transport wind speed of generally 10-15 mph from the northwest.

Because the overall weather pattern has not varied greatly, smoke impacts today are expected to continue to be local in nature and similar to the pat few days.  Smoke from the Pioneer Fire will drain into the Upper Treasure Valley this morning with locally heavy impacts within the drainage corridors including Garden Valley and Idaho City before lifting and dispersing to the southeast where it will continue to affect the Ketchum area within the Big and Little Wood drainages.  Once the inversion lifts, stronger surface and transport winds will move the smoke farther east towards the Middle Snake River Plain and Arco Desert.  Tonight, drainage smoke will again enter the entire Treasure Valley, reaching farther west than previously experienced, as well as the Northern Magic Valley and Ketchum/Sun Valley area.  Also expect to see impacts within the Lemhi Valley and Birch Valley, Big Lost, Little Lost, and Pahsimeroi Valley this evening.  Drainage into the Island Park area via the Upper Henrys and into the Lower Henrys will also occur this evening for brief periods of increased impacts.  The smoke within the Upper Snake is unlikely to reach south to Rexburg or Idaho Falls, instead reaching to around Saint Anthony.  

A pattern shift will bring a change to the weather pattern on Friday.  Tomorrow, early morning drainage smoke is expected to be generally light in concentration, but ubiquitous in coverage, extending east from Boise, through Twin Falls and Ketchum south into the City of Rocks area, and east within the Snake River Plain through Rexburg and into Island Park.  After the inversions lift, an easterly component will shift smoke out of the Treasure Valley while importing smoke from fires in Wyoming into the Upper Snake and southwest into the Pocatello region and Southeast and Eastern Highlands.

DEQ Air Quality Forecast and Cautions:

                           

• The Boise Regional Office has extended a Stage 1 Air Quality Forecast and Caution for Boise County. Valid through Thursday, August 18^th at 3:00 p.m.
• The Twin Falls Regional Office has extended a Stage 1 Air Quality Forecast and Caution for Blaine and Camas Counties. Valid through Friday, August 19^th at 1:00 p.m.

View real time smoke monitoring at:  http://www.airnow.gov/index.cfm?action=topics.smoke_wildfires

View DEQ near-real time monitoring at: http://airquality.deq.idaho.gov/

The USFS installed monitors near Stanley, Idaho and Lowman, Idaho.  Idaho DEQ has installed temporary monitors in Fairfield and Boise (Garden City), Idaho. The information can be found at http://smoke.airfire.org/monitoringReport/#/?date=LATEST&productType=plotTable.

·         Stanley, ID monitor is Stanley-Idaho 75

·         Lowman, ID monitor is Lowman-Jolene Drive

·         Fairfield, ID monitor is Fairfield-Soldier Road

·         Boise, ID monitor is Garden City-Alworth Street

Smoke forecasts are dependent on predicted fire growth and weather.  If conditions change unexpectedly, impacts could occur.  When visibility starts to go below 5 miles, sensitive groups should minimize outdoor activities.  Everyone else should minimize prolonged or physical activity outdoors.  Visit the Idaho Smoke Blog for more information at http://idsmoke.blogspot.com/

Your eyes are your best tools to determine if it’s safe to be outside.  Even if you smell smoke, the air quality may still be good. 

AQI Category	Visibility (miles)
Good	11+
Moderate	6-10
Unhealthy for Sensitive Groups	3-5
Unhealthy	1½  -2¾
Very Unhealthy	1-1¼
Hazardous	Less than 1

How to estimate air quality based on visibility for areas without an air quality monitor or airport visibility estimate:

a. Face away from the sun.

b. Determine the limit of your visible range by looking for targets at known distances (miles).

c. Visible range is when an object you can easily see in the distance disappears.

d. Use the visibility values above to determine the local wildfire smoke category.