Expect smoke in eastern Washington, western WA just about escapes a dose

Smoke in the Methow valley and lower Yakima county is in the process of dissipating over the next few hours as north winds pick up speed. Air quality should be mostly Good around the state through the day, but splotches of Moderate and Unhealthy for Sensitive Groups will return tonight, mostly around Mazama, Winthrop, White Swan, Toppenish, Sunnyside, Hunters and Davenport.

While strong winds blow away the smoke, they have their own agenda:

Some forecast models suggest Canadian wildfire smoke will get caught up in the northerly winds tonight. Winds are expected to shift to the east briefly, bringing this smoke perilously close to the Cascade crest. But this flow pattern is unlikely to persist for long enough to push smoke into western WA. Neither are they likely to blow smoke from fires in western Montana, all the way to far eastern Washington.

Tuesday should see a lighter winds so smoke impacts will be mostly near the fires. Expect Good air statewide with a few areas of Moderate overnight into Wednesday.

7/18/2017 Smoke in Northern WA coming in from large BC fires

The smoke issues we are seeing in parts of Washington are due to large areas of wildfire to the north of us in British Columbia where 40,000 people have been forced from their homes. Our blog map shows the widespread fire detects obtained from satellites (zoom out on the blog map or click on the link below it that says "full map"). They may get some rain by Thursday. All the best to our northern neighbors.

Some news on the fires here:
http://www.npr.org/sections/thetwo-way/2017/07/18/537852651/wildfires-rage-through-british-columbia-forcing-40-000-from-their-homes

More smoke in north Central WA than expected

Contrary to expectations, some smoke from BC wildfires did mix down to the surface yesterday. Air quality hovered between Moderate and Unhealthy at several locations in northern Washington since Monday morning.

Here's the satellite picture from Monday afternoon. White streaks are clouds, light grey patches are smoke and red dots are fire locations.

Not expecting a strong wind shift through Wednesday evening, so northern WA should continue to see more of the same today, although smoke in northern Whatcom county could start clearing sooner. Air quality in many communities of northern Okanogan, Ferry, Stevens and Pend Oreille could degrade to Unhealthy levels today and tomorrow. Some marginal relief is possible in a few areas tonight.

Winds pick up and change direction by Wednesday night but this is a mixed blessing because it brings the risk of dry lightning, which could mean new wildfires. A Red Flag Warning has been issued to address this. Blowing dust on Thursday morning is likely across the Columbia Basin.

More fires and a little more smoke

Numerous fires burning in eastern WA, the largest of which is the Snake River fire near Pomeroy. Air quality in the Lewis- Clark valley has been poor over the last two days and is likely to hover between Moderate and USG over the next few days.

The NOAA HMS Fire and Smoke satellite image shows light smoke from Canadian and Alaskan wildfires over Washington state, but most of it remains aloft. Not expecting strong downward mixing this week so very unlikely that we'll have to inhale much of it. And no, it wont be dense enough to cause spectacular sunsets.

Light north winds are expected across the Columbia Basin today, meaning smoke is likely to drift into the basin. Winds will be driven by daytime heating/ nighttime cooling through Wednesday so not expecting smoke to travel very far from its original sources. Air quality should be mostly Good statewide, except close to fires when periods of Moderate and USG can be expected overnight, with some clearing during the day.

Living Dangerously in the Era of Megafires - TED Talk

Many of you may have seen the recent presentation by Dr. Paul Hessburg on the Era of Megafires.  In this presentation, Dr. Hessburg provides an explanation of why wildfires have been growing in the the western united states.  Recently, a condensed version of the presentation was made into a Ted Talk which is now on Youtube.  Its called Living Dangerously in the Era of Megafires.  You can search for it by title on Youtube or access it by clicking this link https://www.youtube.com/watch?v=edDZNkm8Mas&t=14s.   Or to see it in person, check out the schedule from North 40 Productions website at http://www.north40productions.com/wildfire.

BC wildfire smoke still affecting north central WA

The Methow Valley is very hazy as shown by the Sun Mountain Lodge webcam.

Pollution levels spiked in many areas in and around over Okanogan county today and has commenced its slow daytime decline.

The fire in British Columbia mentioned in the previous post continues to be the culprit, with smoke mixing to the surface when the overnight temperature inversion breaks. The satellite picture this morning shows smoke pouring down the Okanogan river valley.

Air quality in the area is expected to vary between Moderate and Unhealthy in the area with a slow improvement over the rest of today. Winds are expected to shift to the southwest and help return the smoke back to Canada with a "no thank you" note. But smoke lodged in more sheltered valleys might have a harder time getting scrubbed out, so expect areas of Moderate to USG to persist until tomorrow.

Rest of the state should see mostly Good air for the next few days, except close to some fires where Moderate or USG conditions can be expected during overnight hours.

BC wildfire smoke affecting northern WA

Smoke from a fire near Princeton, BC has been affecting parts of Okanogan, Ferry and Stevens counties over the last few mornings. This afternoon's satellite picture shows smoke from the (circled) fire.

The fine particle pollution monitor in Omak bears out the evidence most prominently. Notice how levels spiked over the last 3 mornings.

This happens when (1) northwest flows overnight transport smoke into the area via the Okan(a)ogan river valley, followed by (2) the inversion layer breaking up as the morning sun heats the ground, and (3) smoke aloft mixes to the surface. But daytime winds switch to the southwest and help dissipate smoke- albeit slowly. 

Expect another round of the same smoke behavior in the north central counties from Sunday to Tuesday. Periods of Moderate and USG air are likely during the overnight and morning hours. Unhealthy air in communities such as Oroville and Tonasket cannot be ruled out.

And finally, be prepared for more fire concerns on Sunday, followed by a progressively hotter work week.

Smoke forecast Friday 7/7- Monday 7/10

Currently air quality is mostly Good statewide, with a few Moderate areas sprinkled in. There are several brush fires burning and air quality is likely to be compromised closer to them.

Of immediate concern is the Red Flag Warning for much of eastern WA today. This graphic from the National Weather Service says it all:

A fair amount of fuels in WA are dry enough to burn, as indicated by the FPI index below (OK nothing like the desert southwest!)

While stronger winds will transport smoke from fires around the Cascade Foothills to parts of the Columbia Basin, fine particle pollution (PM2.5) is likely to be somewhat dispersed and I dont expect air quality to degrade much worse than Moderate later today. However as winds lighten over the weekend, communities such as Wenatchee, Quincy and Sunnyside could potentially see a few hours of Unhealthy for Sensitive Groups (USG) air, mostly at night and early morning. Expect mostly Good to Moderate air in other areas of eastern Washington.

No major storms or winds are expected over the next week. Temperatures are expected to remain close to or just above normal. Firefighting isnt going to be easy so lets do our best to prevent fires.

Residual smoke from fireworks in western WA today

Light winds in much of Washington over the last 2 days caused smoke from fireworks to accumulate in many communities.  The chart below shows fine particle pollution levels spiking after 6PM on the 4th of July. A smaller spike was observed on the 3rd.

Pollution levels are still dissipating and we expect Good air quality to return later today.

Smoke from any new fires that started in the last day, whether due to fireworks or other reasons, will likely be confined to nearby areas as winds are expected to remain light until about Thursday evening. Expect mostly Good air quality statewide, with a few Moderate periods.

Smoke forecast for Independence Day holiday

Biggest concern is the dry, gusty winds expected along the east slopes of the central Cascades through tonight. There is a strong possibility of rapid fire spread and a Red Flag Warning has been issued.

Smoke from fires east and west of Yakima is expected to blow across the central and northeastern Columbia Basin today but air quality is expected to remain mostly Good, except right by the fires where Moderate or Unhealthy for Sensitive Groups can occur overnight.

As winds die down and temperatures ramp up on and after the 4th of July, smoke from existing and new fires is likely to linger in the area. Some cities in Yakima county could see Moderate or USG conditions at times.

No major smoke concerns are expected in western Washington over this period. Have a safe and happy 4th of July!