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Wildfire smoke remains Unhealthy on Friday but will improve over the weekend

CURRENT UPDATE for Friday, September 18, 2020: Air quality could reach the Unhealthy range of the Air Quality Index at times on Friday and early Saturday before conditions improve significantly – hopefully reaching the Moderate range or better by Sunday.

The improving air quality is due to the long-awaited low-pressure system that will finally arrive this weekend, eventually clearing most of the wildfire smoke out of our area. Because of the vast quantity of smoke pooled up throughout the region, conditions will be slow to improve ahead of the weather system, with southwest winds bringing additional smoke. 

Hourly updates to air quality can be found at spokanecleanair.org/current-air-quality 

Additional information, including ways to protect your health from wildfire smoke, can be found at https://spokanecleanair.org/air-quality/wildfire-smoke

Previous Smoke Updates:

Thursday, September 17: Air quality should be in the Unhealthy range of the Air Quality Index or better most of the time on Thursday with a little more smoke and Unhealthy conditions possible on Friday.

Although conditions could improve today, the return to southwest winds tomorrow ahead of the approaching weather system will bring additional wildfire smoke through our area. 

Wednesday, September 16: Although Hazardous levels of the Air Quality Index are still possible, air quality will likely be in the Very Unhealthy range or better for most of Wednesday and Thursday.

High pressure and poor ventilation continue to trap wildfire smoke in our area. A gradual thinning of the smoke layer along with surface winds could improve air quality a little more today. Depending on the winds and fire activity, however, conditions will likely worsen at times – especially during the overnight hours. 

Tuesday, September 15: On a positive note…..The 24-hour average PM2.5 (wildfire smoke) concentration yesterday (Monday) was 357.5 micrograms with a corresponding 24-hr average Air Quality Index (AQI) of 406, which is lower than Sunday’s record. Still way above the 24-hour, health-based standard of 35 micrograms and still in the hazardous range, but it’s going in the right direction. Just needs to keep going that way. It appears we won’t have significant relief until the weekend. 

Although conditions should slowly improve today and tomorrow, air quality may continue to reach the Hazardous range of the Air Quality Index on Tuesday and Wednesday. When air quality is HAZARDOUS, everyone is more likely to be affected and should avoid all physical activity outdoors.

Winds continue to bring wildfire smoke into our area and an inversion is also trapping high concentrations of particulates. 

Monday, September 14, 2020

Fine particle pollution measured in Spokane’s air yesterday (24 hour average) was 468.6 micrograms/cubic meter of air. This is more than 13 times the national, health-based standard of 35 micrograms/cubic meter of air, 24 hour average, midnight to midnight.

Concentrations of fine particles are converted to an Air Quality Index scale (AQI). 

Fine particles are microscopic in size, measuring 2.5 microns in diameter or smaller. These fine smoke particles can travel deep into the lungs, damaging and scarring delicate lung tissue. Read more about ways to protect yourself from wildfire smoke, including links to many other resources.

How long is this smoke going to last?

The massive smoke plume from the weekend has left our region covered by a thick layer of smoke. Although conditions should begin to improve somewhat this afternoon with the passage of a weak frontal system, poor ventilation combined with the inflow of smoke from active wildfires will cause smoke to remain trapped near the surface. Even as conditions slowly improve, the Air Quality Index may continue to reach the hazardous range at times today and tomorrow. 

Sunday, September 13:

Air quality remains in the Hazardous range today and may not improve until Monday night and into Tuesday when light winds are expected to improve conditions. Smoke is expected to affect air quality at least through mid-week.


Smoke Outlook for September 11-13, 2020: 

Depending on the winds and fire activity, air quality over the next few days is expected to worsen:

Today, Friday, Sept. 11:  Air quality could possibly reach Unhealthy for Sensitive Groups/Orange range or worse of the Air Quality Index (AQI) Learn more about sensitive groups and precautions everyone can take to protect their health. 

Saturday, Sep 12 and Sunday, Sept 13: Air quality could reach Very Unhealthy/Purple or even Hazardous/Maroonat times.   

This worsening air quality forecast is due to poor ventilation and a gradual return to southwest winds, which will transport increasing amounts of wildfire smoke to our area. We will likely see impacts from the pool of smoke trapped against the eastern slope of the Cascades, followed by potential impacts from a very large smoke plume over western Oregon by late Friday.

According to statewide experts, air quality conditions are expected to decline even more on Saturday evening and Sunday. Check back for updates.

Hourly updates to air quality can be found at spokanecleanair.org/current-air-quality 

Additional information, including ways to protect your health from wildfire smoke, can be found at https://spokanecleanair.org/air-quality/wildfire-smoke

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