07/21/14 Idaho DEQ Smoke Forecast

Updated 1000 MDT Monday, July 21, 2014

Valid through Noon MDT Tuesday, July 22, 2014

Smoke Outlook

Most of Idaho has improved greatly since the end of last week with all sites experiencing large improvements on Sunday compared to Friday and Saturday.  Garden Valley continues to see impacts from the Whiskey Complex and has maintained a 24hr AQI of Unhealthy for Sensitive Groups on Friday, Saturday, and Sunday.  Clearing is expected this afternoon across Idaho except in Garden Valley due to the proximity of the Whiskey Complex.  Garden Valley has shown consistent build-up to brief periods of Hazardous until the inversion breaks and clearing brings concentrations back to the Good category.

An upper level low pressure system is approaching the Pacific Northwest which is amplifying a ridge of high pressure over the Rockies.  This will continue to force a stream of monsoon moisture across Idaho today and tomorrow.  There is a chance of light rain and thunderstorms across all of Idaho south of a line running from Hells Canyon to Missoula.  There is a Red Flag Warning for high wind speeds and scattered (30-50% chance) of thunderstorms in the Sawtooth Range with a Fire Weather Watch for the Western Payette National Forest.  Southwest flow aloft today will transport smoke to the northeast today and have a stronger northerly component tomorrow as the low approaches the coast.  Thunderstorms and instability look to continue through Tuesday across all of the state.  Surface winds are forecast to be generally from the west-southwest at 5-15 mph with locally northeast flow in the Treasure Valley and light and variable wind directions in the Clearwater drainage.  Gusty winds are likely near thunderstorms with southern and southeastern Idaho forecast to see gusts near 25 mph.  Mixing heights will range from 2,000-6,000ft AGL today with mid-level moisture capping vertical movement lower than last week.

Smoke impacts today will be high near fires in the Central Mountains.  Transport of smoke from fires burning in Oregon and Washington will be the primary contributors today.  Smoke and haze is likely over most of northern Idaho from I-90 and north due to fires burning in Washington.   The Clearwater and Lower Salmon drainages should also experience some light impacts and hazy skies in the afternoon due to fires in Oregon and the Pittsburgh Fire.  Smoke from the Whiskey Complex is forecast to move to the northeast, likely creating high smoke and haze in the Salmon area.  Finally, the Lower Treasure Valley may also see impacts this evening as nocturnal drainage flow brings smoke into the valley from Oregon.

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

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.  Refer to the Smoke and Health Tab on the Idaho Smoke Information Blog for additional health information. 

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