Heating up today; expect increased fire activity and smoke

Air quality today is forecast to be in the Good to Moderate range. 

Idaho continues to be under a high-pressure ridge. An embedded disturbance will bring a slight chance for isolated thunderstorms over the elevated terrain of north Idaho. Afternoon winds in north Idaho will be from the south-southwest to northwest at 5-10 mph with gusts up to 20 mph near Lewiston. Southern Idaho will see easterly winds in the morning and west-northwest to southwest winds at 5-10 mph and gusts up to 15 mph in the afternoon.

Numerous fires in the western states are creating widespread haze across Idaho. Intense heat today is expected to increase fire activity and could contribute to a smoke column visible in Cascade this afternoon. Near Salmon, smoke impacts will be worse in the morning before improving some in the afternoon, while Lemhi’s air quality will get worse into the evening as smoke begins to settle into the drainages. North Idaho will see widespread light smoke impacts Thursday morning, with the panhandle seeing higher concentrations overall.

HRRR-Smoke Vertically Integrated Smoke initialized 12Z (6am MDT) and valid at 5pm MDT show increased fire activity and smoke production in the late afternoon today. 

Still hot; still hazy

Air quality today is forecast to be in the Good to Moderate range. 

Today, Idaho will remain under a high-pressure ridge. Winds will be from the northwest to southwest at 5-10 mph in the south and south-southwest to east-northeast at 2-8 mph in the north.  

Fires in Central Idaho remain active and continue to cause impacts. Expect hazy skies across most of the state this afternoon with locally higher concentrations near active fires. Smoke from the Four Corners fire has drifted towards the Treasure Valley early this morning and a well-defined plume is expected to develop this afternoon before moving eastward and then swinging back towards the Treasure Valley overnight.  

Canadian FireSmoke initialized 08Z with 00Z WRF meteorology (valid 1pm 0830 MDT) shows hazy skies across most of the state with locally higher impacts this afternoon. 

Hot week ahead; smoky near active fires

Air quality forecasts in the GOOD to MODERATE range.

Today, an upper-level high pressure ridge will build over the state, leading to hot and dry conditions for much of the week. Winds will be from the south-southwest to northeast at 2-8 mph over north Idaho and from the northwest to southwest at 5-10 mph over south Idaho. Low wind speeds will lead to erratic wind directions. 

Smoke impacts will be greatest near active fires, including the Four Corners fire near Cascade and the Moose fire near Salmon. Dense overnight smoke in Cascade area will slowly disperse through the late morning and afternoon but the immediate area will still experience impacts. Northwest winds will help to limit smoke aloft from out of state fires but smoke from local fires is expected to impact portions of south Idaho today while Salmon will experience hazy skies.  

HRRR-Smoke Near Surface Smoke initialized 12z (06am MDT) and valid 3pm MDT shows increased elevated smoke over parts of south Idaho and locally high concentrations near active fires in central Idaho. 

Impacts highest across central Idaho due to large fires on both sides of state

Bluesky surface smoke shows generally light impacts across the state throughout the forecast period with brief hours of increased concentrations over portions of central and southwest Idaho.

Today, 8/26	Good to Moderate	The upper-level trough will depart to the east and a transitory high-pressure ridge will be over most of the state. There is a lingering chance for showers over the panhandle of north Idaho and over eastern Idaho. Winds will be from the southwest to northwest at 5-15 with gusts up to 25 mph over the Palouse and from 20-30 mph over the Middle and Upper Snake River Plain this afternoon. Thunderstorms will have the capability of producing gusty outflows in excess of 20 mph.	Smoke impacts near fires will be greatest, particularly across central Idaho with large fires burning both on the west side and east side of the state. Impacts today will remain over that area with zonal flow shifting smoke generally to the east.
Saturday, 8/27	Good to Moderate	A cold front on Saturday will bring a chance of showers to the Panhandle and central Idaho. This system will also bring a chance for our first snow across the highest peaks in the West-Central mountains.  Surface winds will be from the southwest to northwest at 10-30 mph with gusts approaching 50 mph in central Idaho and into the Upper Snake River Plain.	Nocturnal drainage smoke looks to reach the southern Panhandle early Saturday morning as well as generating hazy conditions over the Lower Treasure Valley and Owyhee County. The active weather on Saturday should limit high smoke concentrations in the state except for areas near active fires once more.
Sunday, 8/28	Good to Moderate	On Sunday, conditions temper with a slight chance for showers over eastern Idaho and central Idaho. Surface winds will be from the northwest to southwest at 5-15 mph with gusts to 20 mph in the Middle Snake River Plain.	Early Sunday morning, there will be patchy smoke and haze over the Lower Treasure Valley once more. Conditions will clear throughout the day Sunday.
Monday, 8/29	Good to Moderate	By Monday, an upper-level ridge will build, leading to hot and dry conditions for the first part of the week. Winds will be from the south-southwest to north-east at 2-8 mph. Low wind speeds will lead to erratic wind directions.	Monday looks to be relatively clear with only light lofted smoke.

Hazy over central Idaho

 Air quality forecasts for today are in the Good to Moderate Category. 

Today, the upper-level trough will begin to migrate to the east, continuing to bring an increased chance for showers over north Idaho and the elevated terrain of south Idaho. Winds will be from the northeast to northwest at 5-10 mph over north Idaho and from the northwest to southwest at 5-15 mph over south Idaho. Gusts from 20-25 mph over the Middle and Upper Snake River Plain will develop this afternoon. Thunderstorms will have the capability of producing gusty outflows in excess of 20 mph.

Smoke impacts near fires will be greatest, and hazy conditions will continue over much of central Idaho today with increased concentrations expected this afternoon. Elevated readings will occur this evening into the Upper Snake River Plain in response to nocturnal drainage. The Palouse and southern Panhandle could see increased impacts tomorrow morning as smoke tracks in from the west-northwest.

HRRR-Smoke Vertically Integrated Smoke initialized 12Z (06am MDT) and valid 00Z (06pm MDT 08/25) shows generally light impacts with locally high concentrations over the Central Idaho Mountains.

Haze continues

Air quality forecasts for today are in the Good to Moderate Category. 

Today, the upper-level trough will retrograde into the Pacific Northwest, bringing an increased chance for showers over north Idaho and the elevated terrain of south Idaho. Winds will be from the northeast to northwest at 5-10 mph over north Idaho and from the northwest to south-southwest at 5-10 mph over south Idaho. Thunderstorms will have the capability of producing gusty outflows in excess of 20 mph. 

The shift to northeast winds over the panhandle will bring in periods of light smoke to the area today; however, scouring should be expected near any storm activity. Smoke impacts near fires will be greatest, and hazy conditions will continue over much of north and central Idaho into Thursday.

HRRR-Smoke Vertically Integrated Smoke initialized 12Z (06am MDT) and valid 18Z (12pm MDT 08/25) shows light impacts with generally light, lofted smoke covering the state.

Hazy conditions over most of state

Air quality forecasts for today are in the Good to Moderate Category 

Today, an upper-level trough will be situated along the Canadian border, bringing showers to the elevated terrain surrounding the Panhandle as well as a slight chance for showers over the Eastern and Southeast Highlands. Winds will be from the northwest to southwest at 5-10 mph. Thunderstorms will have the capability of producing gusty outflows in excess of 20 mph. 

An active weather day will limit smoke impacts to areas near active fires, affecting locations near Salmon and North Fork where conditions remain dry and warm. Hazy conditions aloft will be present over much of the state tonight and through the forecast period.

HRRR-Smoke Vertically Integrated Smoke initialized 12Z (06am MDT) and valid 18Z (12pm MDT 08/24) shows light impacts with generally lofted smoke covering the state.

Air Quality Advisory Lifted for Lemhi and Custer Counties

 

Locally intense concentrations near active fires

Air quality forecasts for today are in the Good to Unhealthy for Sensitive Groups Category.

Today, an upper level trough will pass through Idaho, bringing showers to the elevated terrain surrounding the Snake River Plain and much of Central Idaho.  Winds will be from the northwest to southwest with easterly winds within the Middle Snake River Plain at 5-10 mph.  Thunderstorms will have the capability of producing gusty outflows in excess of 20 mph.

An active weather day will limit smoke impacts to areas near active fires, affecting locations near Salmon and North Fork, as well as in the Panhandle along the Canadian border.  This evening will bring draining smoke across the Camas and Weippe Prairies reaching as far west as Lewiston by 6am MDT tomorrow morning.  Lingering smoke will lift with the breaking of the morning inversions. Smoke also drains south within the Purcell Trench tonight and tomorrow morning reaching Coeur d’Alene by 5am MDT.

HRRR-Smoke Vertically Integrated Smoke initialized 12Z (06am MDT) and valid 11Z (05am MDT 08/23).  This shows locally intense concentrations with downslope drainage across the Panhandle and Central Idaho.

Air Quality Advisory Issued for Lemhi and Custer Counties

 

Smoky and hazy this weekend

Air quality forecasts for today are in the Good to Unhealthy for Sensitive Groups Category. 

Today	An upper-level trough will pass through Idaho, bringing showers to the elevated terrain surrounding the Snake River Plain.	Smoke will continue to affect the Central Idaho Mountains and expand northwards to the Canadian Border today. Smoke will lift with an active weather pattern before settling back into valleys after sunset tonight.
Saturday	Friday’s pattern continues and expands in coverage to reach as far north as a line running from Grangeville to Missoula.	Portions of the southern Panhandle will clear Saturday morning, while the northern Panhandle will experience hazy conditions again. Central Idaho will see impacts east of a line running from McCall to Kalispell.  There will be drainage smoke into the Lower Snake River Plain west of Mountain Home late Saturday night which will lift and clear by noon Sunday.
Sunday	The system tracks east and out of the area, leaving a slight chance for showers along the Bitterroots, Eastern, and Southeast Highlands.	Impacts on Sunday look to be less than Saturday, with a focus on the area around Lemhi and Custer Counties increasing and expanding after sunset.
Monday	An approaching system will bring a slight chance of showers over all of northern Idaho and the Eastern Highlands.	This expanded coverage will affect the Snake River Plain west of Twin Falls and north to Lewiston and Dworshak before clearing throughout the day Monday.

Video: 0.5/0.15deg Bluesky indicates diurnal smoke ebbing and flowing across central and northern Idaho with increased concentrations in the evenings and lifting in the afternoons.

Increased smoke production and transport expected tomorrow

Air quality forecasts for today are in the Good to Unhealthy for Sensitive Groups Category.

Today, the upper-level ridge will shift slightly east in response to an upper-level disturbance approaching from the southwest. Cloud cover and smoke aloft will keep temperatures suppressed slightly over southern Idaho. There will be a chance for isolated thunderstorms over southern Idaho along the ID/NV border. Surface winds will be from the northwest to northeast. Surface wind speeds will be from 2-8 mph today. The strength and positioning of the ridge of high pressure will limit smoke transport but keep activity high. Conditions will change considerably tomorrow with a pattern change and the upper-level low pressure system tracking over Idaho. Expect increased fire activity and increased smoke production and transport.

Smoke will continue to affect the Central Idaho Mountains the greatest today with high concentrations in Lemhi County, over the intersection of Custer, Valley, and Boise Counties, Valley, and Adams Counties. Elevated smoke concentrations will develop over the northern Panhandle from the Canadian border and south to Kootenai County. Smoke in Central Idaho will begin to expand in coverage north to Benewah County, south to Payette County, and west to the Oregon border by tomorrow morning. Late in the forecast window, widespread smoke covers the northern 2/3rds of the state with increased coverage and concentrations after that period.

HRRR-Smoke Vertically Integrated Smoke initialized 12Z (06am MDT) indicates increasing smoke coverage and locally high levels of concentrations in the vicinity of fires.  This coverage and concentration expand tomorrow and so expansive deterioration should be anticipated.