Tuesday, September 29, 2020

Mamma mia! Here we go again? Not so fast.

There has been some speculation that another bout of Californian smoke will overrun western WA again this week. Thankfully, it now seems like those concerns are a bit overblown. 

Highlights

  • Starting Tuesday evening, there will be a little smoke in western WA. Not expecting populated areas to get worse than Unhealthy for Sensitive Groups, although Moderate will be the most common.
  • Higher elevations will see more smoke. 
  • This will not be a prolonged event. Please keep an eye on the smoke forecast
  • Get ready to enjoy some resplendent sunsets
  • Hardly any impacts expected east of the Cascades

What does the latest satellite picture (10:20AM today) look like?


Smoke is indeed traveling northbound along the Oregon coast now.

What do the models say?

They have their own opinions, some with more merit than others. Discussing with the National Weather Service offices and air quality agencies, we feel that the HRRR smoke model injected too much smoke into the air and is trying to offload a generous portion of that in our backyard. We're not buying it. Most other models are (i) working with less smoke and (ii) keeping a lot of it aloft. This is consistent with satellite imagery, ground based air quality monitoring data and the vertical temperature structure of several models. 

Here's what different models think the mixing heights in Olympia will be for the next 72 hours. Black line is the mean of them all. 

This means vertical mixing through the atmosphere is confined to a shallow layer, ~400m today at most, 700m max tomorrow and back to about 400m on Thursday. Most of the smoke will be 1-3km above us, so we won't be tapping into the overhead smoke reservoir all that much. 

This is a good example of a temperature inversion working in our favor by not allowing smoke aloft to mix down. But inversions also trap pollutants released at the surface within a shallow layer, so we still have to deal with our own gunk in addition to whatever little smoke mixes down.

Will the smoke aloft interfere with Aurora Borealis viewing?

Probably, but there needs to be a good aurora. We returned home disappointed at 2AM this morning and tonight's geomagnetic activity is expected to be no different than yesterday. If a faint glow does appear low on the northern horizon, the smoke will filter some of it out. Going to higher terrain won't help much. 

30 comments:

  1. Thank you for the update, appreciate it. I think we're all on edge about smoke lately, so it's a relief that this one won't have such a big impact on our air quality.

    I'm planning a camping trip later this week, do you think high elevations in the North Cascades will see lower air quality? I would imagine it's probably hard to say, I just wanted to avoid spending a bunch of time in an area with smoky air. Thank you!

    ReplyDelete
    Replies
    1. Hello Reed, the winds are not expected to die down like they did earlier, but will keep the smoke moving along. We think the smoke tap will shut off by the end of the week due to directional shifts. Plus we're dealing with much less smoke than before. So while I dont expect the N.Cascades to see very smoky air by the end of the week, it will be a good idea to be prepared for some smoke and slightly obscured views. Have a good trip!

      Delete
    2. Thanks, I appreciate your response. I will keep following the forecast and be flexible about my plans. Seems to be the theme for 2020.

      Delete
  2. I'm loving the new current conditions map with forecast overlay. Very nicely done!

    ReplyDelete
  3. Hello. Thanks for the update. Forecast still shows Bellingham with good air quality tomorrow. Is this expected to change? Also, this isn't expected to be as prolonged, but what's the estimated return to normal date? Thanks.

    ReplyDelete
    Replies
    1. SCM, Moderate is probably where you will land if it changes. We think it would be over before the end of the work week

      Delete
  4. You mention that higher elevation will see worse air quality tomorrow - do you have more details on that? I'm planning a trip to Mt Rainier tomorrow (Wednesday) so I was wondering which areas/which elevations will see better air quality than others.

    ReplyDelete
    Replies
    1. Hi Golish, the exact impact heights of smoke is hard to predict. Assuming you're going to Paradise and not higher, then I'd say prepare for periods of USG air and a slightly obscured view.

      Delete
  5. I’d say nice to hear from you, but in this context not so much! If moderate is expected, than can we leave windows open if we aren’t prone to moderate air conditions ?

    Thank you!!

    ReplyDelete
    Replies
    1. Hello, welcome back and yes I think you can leave the windows open for now

      Delete
  6. Hello, thanks for the update. Any guess on when we will finally be done with 70s, 80s, and high pressure ridges? Mid-late next week predictions seem to be cooling down a bit, would that be a resonable guess? A bit drained from all this smoke... 50s and 60s are very welcome!

    ReplyDelete
    Replies
    1. Hi, western WA should have the respite from the heat that you're yearning for by this weekend and then again by mid week. FYI high pressure builds on & off year round; just that the sun angle is low in fall through spring, so it doesnt warm up as much.

      Delete
  7. Do you know if the east side of the mountains (Leavenworth-Winthrop area) is supposed to see any of this smoke?

    ReplyDelete
  8. Thank you for your wonderful insight throughout this year's smoke season! At what elevation approximately will the smoke get worse on the Olympic Peninsula? And when will the winds shift enough to see significant clearing?

    ReplyDelete
    Replies
    1. Well several ground level monitors along the Olympic coast are already showing Moderate air. We dont expect it to get any worse than USG (Orange) at the higheer elevations. Satellite picture doesnt show a very dense layer of smoke aloft. Exactly at what height the Moderate becomes USG is hard to tell. Clearing will likely come by Friday

      Delete
    2. Thank you! This is very helpful.

      Delete
  9. Fairhaven bellingham seem grayish red sky and smells Smokey with air purifier on high is this considered moderate. What does yellow moderate mean for Sam patients???

    ReplyDelete
  10. Just wanted to know if you would advise opening windows at night. I just don't want things getting worse, over night, and being stuck for quite some time with poor indoor air. Thanks, in advance, and for all you do!

    ReplyDelete
    Replies
    1. We're not expecting a huge degradation of air quality overnight, but it wont get better either. "Bad" time under these circumstances is in the morning when the nighttime surface inversion breaks and some smoke aloft mixes down. But everything already at ground level + any wood stove emissions will remain at the surface overnight.

      Delete
  11. I am also trying to improve my understanding of how fires are being detected and so on. Does anybody know if commercial planes that fly over the states just naturally transporting people and cargo are taking pictures of our forests (I could not find anything on that)?

    ReplyDelete
    Replies
    1. Most are detected by satellites that look for larger areas substantially hotter than the surroundings (aka hotspot detection). Presence of clouds can interfere with this at times.

      Delete
  12. The map had been blank (solid grey) for several days. Will it return soon?

    ReplyDelete
    Replies
    1. Proche, we did upgrade the map to show both the monitoring data and forecast, and it can be a bit slow to load. However it does work. Perhaps your browser's security settings are preventing it from loading? Try using another device/ computer. If using a mobile device, scroll to the bottom and click "Show web version".

      Delete
    2. Thanks for reply Ranil. Tried M Edge and it loaded so went back to Chrome and added your URL to the always allow cookies and it loaded. Such an informative website - thank you.

      Delete
  13. We've got smoke in ellensburg, kittitas valley. You can smell it with a red sun at sunrise...perhaps coming in via SE? Any thoughts?
    Suzy

    ReplyDelete
    Replies
    1. As forecast, expect Moderate air due to a mix of some smoke from CA fires and local woodsmoke getting trapped beneath the inversion.

      Delete
  14. I just want to say thanks for the fantastic blog. I live in White Rock BC, so just a long golf drive from WA state but I regularly use your site for information during fire season.

    ReplyDelete
  15. Hi, can you give us more of an update? With no comment the forecast here and on AirNow.gov has changed to continue to have bad air quality tomorrow and through saturday. It's making me worried that we will have a repeat of a few weeks ago when stagnant weather kept the smoke around for days. The air quality just keeps getting steadily worse in Seattle!

    ReplyDelete

We monitor this site during business hours, Monday through Friday, 8AM to 5PM. We encourage your questions, comments, and feedback. We ask that everyone be respectful of the opinions of others, and avoid comments that are defamatory, inappropriate or off-topic. If you have an emergency, please call 911.

We moderate all comments to prevent spam. Your comment will publish upon review