Friday, September 11, 2020

The Smoke Forecast and Its Extreme Variations

Note:  my new podcast on the smoke situation is up (information at the bottom)
__________________

What a difference a few days make.  Here is the view of Seattle from the SpaceNeedle PanoCam at 8:30 AM this morning.  Apocalyptic.
.

Yesterday was a bit hazy, but far better:


And four days ago (September 7th) you could see Mt. Rainier.


Portland this morning is truly scary:


A visible satellite image for 9:46AM  tells the story. Shallow smoke over Puget Sound and Northwest Washington and DENSE smoke over SW Washington and Oregon.  Interestingly, many of the high elevations are smoke free.  I will tell you why in a second.


Air quality went bad overnight, the EPA AirNow sites at 10 AM shows unhealthy levels across Puget Sound (red), VERY UNHEALTHY (purple) levels towards the coast, and HAZARDOUS (purple) levels in the Portland area.


Interestingly, at many locations in Washington you can get above the smoke (above around 4000 ft), as illustrated by the image from the Crystal Mountain cam near Mt. Rainier (see below).  You can see the low-level smoke layer!


Why is the air clean at elevation? 

Because there is a strong inversion (temperature increasing with height) below roughly 4000 ft and inversions act the like barriers that prevents the smoke form mixing vertically.   To illustrate, here is the temperature/dew point sounding at 5 AM this morning on the WA coast (Forks).  Red is temperature and height is in pressure (700 is roughly 10,000 ft, 850 roughly 5000 ft).

Mama Mia!  That is a strong inversion.  There is a shallow marine layer (1000-950) with a 12C warming above.


So what is going to happen?  The recent HRRR smoke forecast for 2 PM this afternoon shows poor conditions over Portland and into Puget Sound (purple colors) and unhealthy condition (red) over the rest.  I am not going running today!


Not much better at 11 PM tonight, except perhaps on the Washington coast.  But getting MUCH worse east of the Cascade crest as increasing westerly winds push the smoke to the east.


Skipping ahead to Sunday morning at 3 AM, there is significant improvement along the entire coast, modest improvement over Seattle and Portland (although still smoky) and MUCH, MUCH worse over eastern WA and Oregon.   I hope the grapes are harvested.   Conditions in Spokane and the Tri-Cities will not be pleasant.


________________________________


My latest podcast:

20 comments:

  1. Is this patch of smoke likely to stay intact as it drifts west across the US (and impact, say, midwestern states), or does smoke typically dissipate substantially after traveling a certain distance?

    ReplyDelete
  2. Where is the best place to escape the smoke this weekend? The coast? Or the mountains?

    ReplyDelete
  3. Time to hole up/batten down and use the weekend to read up/binge watch your favorite whatever and just decompress. The air pretty much has a texture to it, as in it can be tasted. Best to AVOID. Bummer it hit on the weekend but at least for most the weekend means going outside is optional.

    ReplyDelete
    Replies
    1. "Time to hole up/batten down and use the weekend to read up/binge watch your favorite whatever and just decompress."

      Finally, an excuse to do what we've been doing for the past six months.

      Delete
  4. Where is the best place to escape the smoke this weekend? The coast? The higher alpine?

    ReplyDelete
    Replies
    1. He posted some very convenient maps and made special note that 4000+ ft was clear air, so...

      Delete
    2. Will the alpine continue to be saved from the smoke with this push East over the crest?

      Delete
  5. I've been wondering if other people have been confused about the differences between AQI and ug/m3, which are both reported at various places. After some study, I now understand that the AQI is an index that is supposed to help the public understand the threats to health, and is based on the actual measured PM 2.5. (See https://aqicn.org/calculator/). Even in this blog (i.e., https://cliffmass.blogspot.com/2020/07/the-jury-is-in-personal-fireworks-alone.html) I saw the two measurements juxtaposed, with 2019 levels reported as reaching 102 ug/m3 and 2020 levels reaching 120 on the AQI (WAGA). The blog concluded that 2020 pollution was greater than 2019 pollution. However, 102 ug/m3 is 170 on the AQI. And 120 on the AQI corresponds to 43.5 ug/m3.

    ReplyDelete
  6. Cliff, could you post a link to the models you are using? I am not seening the longer duration HRRR-Smoke Forecast on the NOAA Website, just ones extending out roughly 24 hours into the future. Thanks!

    ReplyDelete
    Replies
    1. I think this is it! https://rapidrefresh.noaa.gov/hrrr/HRRRsmoke/jsloopLocalDiskDateDomainZipTZA.cgi?dsKeys=hrrr_smoke_jet:&runTime=mostrecent&plotName=trc1_t1sfc&fcstInc=60&numFcsts=49&model=hrrr&ptitle=HRRR-Smoke%20Model%20Fields%20-%20Experimental&maxFcstLen=48&fcstStrLen=-1&resizePlot=1&domain=t1

      Delete
  7. How long is the inversion expected to last? Will the air at high elevations still be clear tomorrow night?

    ReplyDelete
  8. I've been wondering if other people have been confused about the differences between AQI and ug/m3, which are both reported at various places. After some study, I now understand that the AQI is an index that is supposed to help the public understand the threats to health, and is based on the actual measured PM 2.5. (See https://aqicn.org/calculator/). Even in this blog (i.e., https://cliffmass.blogspot.com/2020/07/the-jury-is-in-personal-fireworks-alone.html) I saw the two measurements juxtaposed, with 2019 levels reported as reaching 102 ug/m3 and 2020 levels reaching 120 on the AQI (WAGA). The blog concluded that 2020 pollution was greater than 2019 pollution. However, 102 ug/m3 is 170 on the AQI. And 120 on the AQI corresponds to 43.5 ug/m3.

    ReplyDelete
  9. I went hiking near Snoqualmie Pass today and it was much better there, although conditions worsened throughout the day just as the smoke forecast suggested they would. It was nice to get above most of the smoke for a few hours!

    ReplyDelete
  10. I live in Clark Co, just north of Portland. I was just looking at the air quality around the area on the Weather Underground site and the nearest station to me that measures air quality has it at 500, which is as high as the scale goes.

    We have been running the fan on the HVAC constantly and it isn't keeping up. We're also having a nuclear winter sort of phenomenon. Temps have been in the high 70s and low 80s and Friday had a high of 64.

    I've dealt with fire smoke before, but the air was always moving a bit and the smoke didn't accumulate like it is now. This is way worse than anything I've seen and we've had large fires closer than the nearest one to us now.

    ReplyDelete
  11. I live in Clark County (just north of Portland) and the smoke here is the worst I've ever encountered. I was looking at the air quality around here on Weather Underground and the nearest station to me is showing air quality of 500. The scale doesn't go any higher!

    I've lived in the NW since the late 80s (both Seattle and Portland area) and grew up in Los Angeles during the worst smog. This is the worst I've ever seen. A few years ago there was a big wild fire that was closer to us than any of the current fires (it snowed ash) and the air quality then wasn't as bad as it is now.

    We've been running the fan on the house HVAC constantly for a couple of days and it isn't keeping up. I set up some humidifiers, even though the humidity is decent to try and trap some of the particles in the air. It helped some, but the house still smells like smoke and it's been getting worse the last 24 hours.

    We've also experiencing a sort of mild nuclear winter. Normally temps are in the 80s and Thursday's high was 92, but the high on Friday was 64. It's surreal here.

    ReplyDelete
  12. The Enumclaw and Issaquah DOE air sensors must be malfunctioning, correct? Although, I am at about 450 ft. elev. in Kent E. Hill ... it feels as if we may be just above the murk. The moon is almost white and there is dew on my cars.

    ReplyDelete
  13. My friend Lucy, from listening to your podcast(s), gets the impression that you are a climate change denier. Please explain occasionally that this is nonsense. She is very intelligent but doesn't have the scientific background to properly interpret complex science backed weather information. Thanks, David.

    ReplyDelete
  14. "These are not just wildfires. They are climate fires," says Gov. Inslee. Various fire officials say they're human-caused and weather-enhanced, but those claims don't further the Climatastrophist cause.

    ReplyDelete
  15. Hey Cliff, I enjoy your blog. I'm in the seattle area and have a question: does the smoke dampen sound? Obviously when there's snow on the ground and when it's snowing big wet flakes, it definitely muffles sound outdoors. Yesterday I was walking around my neighborhood, and it definitely *seemed* quieter with the dense smoke, but I'm wondering if that's just my imagination or a real phenomenon... I'd bet you're the right person to answer the question.

    ReplyDelete