09/05/2017 Idaho DEQ Smoke Forecast

Air quality is forecast to continue to remain in the Good to Hazardous air quality category for the 24 hour AQI across the state today; however hourly readings will likely be much higher at times.  Most recent monitor observations are currently reading in the Moderate to Very Unhealthy level for an hourly reading.  This past weekend saw conditions deteriorate each day to levels that reached the Very Unhealthy Category for a 24hr AQI over the Labor Day holiday.   Areas currently being impacted most severely are across the Panhandle and south to the Clearwater drainages where conditions are in the Very Unhealthy and are forecast to be in the Hazardous at some locations. Ambient, lofted regional smoke is currently interspersed across southwest and southern Idaho and is providing consistent, elevated readings across the area to Unhealthy readings and Unhealthy forecast AQI conditions today.

                                                                                                                                            

The upper level ridge will continue to sit over all of Idaho and drive light, easterly winds with a warm mid-layer that will cap mixing and vertical movement of the smoke.  Surface winds will be from the northeast to northwest with locally southeast winds within the Treasure Valley at 5-10 mph.  Skies will be sunny when not obscured by smoke.  Mixing heights will range from 2,000-5,000 feet AGL across all of Idaho today.  Transport winds will be from the northeast to northwest at 5-10 mph.  Temperatures will remain high, although dense smoke coverage will potentially limit maximum temperatures as we enter a prolonged blocking ridge pattern through Wednesday at the earliest.    By Wednesday, a mid-level high pressure system will settle over the intersection of WA/OR/ID and provide a northerly-northwesterly component to the region.

The easterly winds at the surface are expected to persist through at least Wednesday with light winds continuing through Thursday.  Expect substantial and continued deterioration of the air quality across the Idaho Panhandle and Central Idaho.  Southern Idaho should also expect to see continued impacts through today and Wednesday.  Due to the light winds and consistent easterly wind direction, improvements to air quality are not expected today through Wednesday.  Beginning Thursday, conditions may allow for limited improvement over south Idaho.

DEQ Air Quality Forecast and Cautions:                      

·         Idaho DEQ has issued a state-wide Stage 1 Forecast and Caution for all counties.  This will be re-evaluated Thursday, at 10am MDT.

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 has installed a monitor in Challis. The information can be found at the airnow page above

·         Challis, ID monitor is: Smoke 19

·         Riggins, ID monitor is: Idaho 1001

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.