September 09, 2020

Fire and Smoke Update

The visible satellite image this morning shows huge contrasts over the region.  Modest smoke over the western WA lowlands, a bit denser smoke over the western side of the Columbia Basin, and dense, horrific smoke over western Oregon from a series of active fires on the western slopes of the Oregon Cascades.  Also note a lack of smoke at higher elevation over Washington (hint: you could take a nice higher-elevation hike in clean air).

The event in western Oregon is huge, involving hundreds of thousands of acres.

Current air quality (see below) is poor (red and purple) from Wenatchee to Omak, and hazardous in the Willamette Valley.

Satellite technology offers powerful tools for determining where active fires are location, based on the radiation emitted by fires.  Here is an image showing active fires (orange color) and smoke from the NOAA/NWS GOES-17 satellite.  Huge, active fires on the western slopes of the Oregon Cascades, with massive smoke plumes blowing to the west.   Importantly, there is little fire activity across Washington State. 

Most of the major fires earlier this week were mainly grass fires that burn quickly in a flashy way.  They are accessible to firefighters and generally stop when they hit some kind of obstacle (e.g., a river or irrigated agricultural land).  The fires in Oregon include forest with huge amounts of fuel and driven by the persistent easterly winds.

So what is going to happen to the fires and the smoke?   

The key issue is wind.

During the past few days, we have had unusually strong and persistent easterly (from the east) winds in the lower atmosphere over western WA/Oregon and the Cascades.   A plot of winds, temperature, and heights (think pressure) at roughy 5000 ft (850 hPa pressure level) this morning shows the situation clearly (below, click to enlarge).  Those little barbs provide the wind speed and direction.  Higher pressure/heights in eastern Washington, lower to the west.

This flow pattern is moving smoke over the mountains at low levels and will continue during the day, so expect the current air quality to continue for a while.  But northerly winds will develop this afternoon over Puget Sound, which will bring some cleaner air into Seattle later today.

I will end by showing you the predicted near-surface smoke from the NOAA HRRR model.

This morning at 11 AM, there is mega-smoke over western Oregon and modest smoke over western WA.

But things improve a bit over Puget Sound during the day and by 11 PM, the air may not be too bad over Puget Sound.

Unfortunately, overnight (8 AM Thursday shown) more (but modest) smoke is predicted to move back over Puget Sound.  Interestingly, Portland is not doing too bad with flow through the Columbia Gorge and the Oregon fire smoke staying to the south.  And yes, California is terrible as well.

On Friday, the marine air will start moving in, which should improve our air quality, if we can avoid getting hit by the Portland smoke.  More on that later.

A big question that some folks are asking is:  how much of this is due to global warming.  I will deal with that in a future blog.  But let me give you something to think about.   The big fires this week were associated with both warm/dry conditions and very strong northerly and easterly winds.  To determine whether global warming could contribute to the recent events, you have to analyze each mechanism separately.

KNKX surrenders to cancel culture. More information here.

If you want to support this blog you can do it through Patreon:


  1. On the "global warming" comment. Let's steer away from politics, and talk about contributions to the various areas that affect our climate. The thing that kills me about "Climate change" people is the associate that "everything" is human provoked, and likewise what kills me about the "Climate deniers" is the absurdity that the way we are polluting earth has 'zero' effect on our planet.

    The truth is we have a relationship with earth, she affects us, and we affect her, specially with our capabilities times ~7.8 billion people and the very large footprints each of us carries.

    The question and answer isn't "Is this due to human made climate change or global warming", it's "what can we do to help nature continue to be nature" and prevent the human side from being any variable in the equation.

    1. "what can we do to help nature continue to be nature" and prevent the human side from being any variable in the equation.

      Aren't we humans and what we do part of "nature"? If yes, then how can what we do not be natural? If we have reproduced ourselves to 7.8 billion, then wasn't it natural for us to have done that?

  2. Wow that first satellite image is a stunning visual, I love how it outlines the river basins and gives a sense of how these easterly winds rocket through the pathways of least resistance (US2, I90, etc). I can see clearly where all the highways should sit.

  3. We live in the mid-Columbia Gorge near White Salmon, and were on high alert because of all the warnings. Thus far, the situation has been spotty. Some fires, especially near Yakima and one in Wasco County, OR, have caused a smoky Monday afternoon, but that's about all. My handy Davis Weather station shows that the maximum wind speed here was 30 mph that afternoon, and 20 mph yesterday. All in all, this seems to be much more of a western slope event.

  4. Regarding your last point (maybe I should wait for that future post!), my understanding is that bad fire seasons, heat waves, cold waves, drought, etc., have always happened. To control all variables and claim a single particular extreme weather event is worse due to climate change might be true, but it isn’t currently possible to determine. Instead, the statistical frequency will show the effect, like 100 year floods happening every ten years. I’m I understanding this correctly?

  5. 500,000 acres burned in Washington so far. Not as many as 2015 but still really bad. Wether fossil fuel burning has helped exacerbate climate change we don't know, but we do know polluting the atmosphere with fossil fuels has led to staggering lung cancer rates regardless, and for that you should speak out.

    1. Please verify the "staggering lung cancer rates." Or given that you're in Seattle and perhaps rather loosely tethered, did you just make it up? Nah, couldn't be. LOL

    2. The American Cancer Society’s Cancer Prevention Study II, which began in 1982 and enrolled 1.2 million participants in the U.S., has drawn links between regional differences in air pollution and increased risk of lung cancer, Bhatti said. That’s true even among nonsmokers. A 2011 analysis from that large study saw that increases in the type of air pollution known as particulate matter — tiny, airborne particles given off by wildfires, industry and traffic — also increased deaths due to lung cancer among those who had never smoked.

  6. Our own Gov. Insley has already confirmed climate change as the cause of the extensive fires,ruling out all potential causes. It's possible, of course, but I'm skeptical.

  7. Oregon is in fairly deep trouble this morning, areas less than thirty minutes away from me are either on high alert and/or in the process of being evacuated. Tremendous losses of property and now we're learning about losses of life as well. You can barely see right now outside of my place, the smoke is that pervasive. Many 911 calls are not being answered, because all available personnel are already out fighting the blazes that have erupted over the past 48 hours. The Columbia gorge fire a few years back was bad, but this event is of a multitude worse.


Please make sure your comments are civil. Name calling and personal attacks are not appropriate.

More Rain for the Northwest is Good News for Wildfires

After a very pleasant dry spell, another rainy period is ahead for the western side of the region and the Cascades on Friday and Saturday.  ...