Thursday, August 10, 2017
Will smoke start to clear by Friday? Yes ± maybe
Ah the challenges of communicating scientific uncertainty!
Wednesday's air quality conditions remained pretty close to a repeat of Tuesday. Thursday will plagiarize from Wednesday. There is a reasonable chance that gradual improvements in western WA will commence by Friday afternoon. Eastern WA will have to wait a little longer. More on all that further down.
For today, expect mostly Good to Moderate air in southwest and northwest WA, while areas from Lynnwood down to Olympia can expect Unhealthy for Sensitive Groups or Unhealthy air at times. No change to the pessimistic forecast for most of eastern WA: Unhealthy for Sensitive Groups or worse 😢
Ground level ozone (aka smog) concerns (which we blogged about recently) persist, exacerbated by wildfire smoke. Locations in the Cascade foothills communities of east King and Pierce Counties and the Tri Cities recorded high levels of ozone this past week. An air quality advisory for smog has been issued.
However with north-northeast winds likely to let up for a while, Thursday will hopefully be the last day in a long stretch of high ozone days. At least for now.
About that reasonable chance: here are the forecast windspeeds shown by all the main weather models, for Seatac airport from now through 5PM on Sunday (times are in GMT, so subtract 7 hours for PDT; shaded times are overnight hours). The thick black line is the average of them all (known as the "ensemble mean" in geek speak).
Because many models agree that the slight uptick in speeds overnight Friday will remain through Sunday, we're more confident that smoke will start to disperse by then. Winds wont be terribly strong, so clearing will not be rapid.
The same plot for Spokane airport suggests that eastern WA will have to wait an extra 12-18 hours before clearing commences.
And, none of the major models are suggesting a return to this ridging pattern within the next week. Meaning BC wildfire smoke is unlikely to blanket the state anytime soon. Just yet. We hope.
Wednesday's air quality conditions remained pretty close to a repeat of Tuesday. Thursday will plagiarize from Wednesday. There is a reasonable chance that gradual improvements in western WA will commence by Friday afternoon. Eastern WA will have to wait a little longer. More on all that further down.
For today, expect mostly Good to Moderate air in southwest and northwest WA, while areas from Lynnwood down to Olympia can expect Unhealthy for Sensitive Groups or Unhealthy air at times. No change to the pessimistic forecast for most of eastern WA: Unhealthy for Sensitive Groups or worse 😢
Ground level ozone (aka smog) concerns (which we blogged about recently) persist, exacerbated by wildfire smoke. Locations in the Cascade foothills communities of east King and Pierce Counties and the Tri Cities recorded high levels of ozone this past week. An air quality advisory for smog has been issued.
However with north-northeast winds likely to let up for a while, Thursday will hopefully be the last day in a long stretch of high ozone days. At least for now.
About that reasonable chance: here are the forecast windspeeds shown by all the main weather models, for Seatac airport from now through 5PM on Sunday (times are in GMT, so subtract 7 hours for PDT; shaded times are overnight hours). The thick black line is the average of them all (known as the "ensemble mean" in geek speak).
Because many models agree that the slight uptick in speeds overnight Friday will remain through Sunday, we're more confident that smoke will start to disperse by then. Winds wont be terribly strong, so clearing will not be rapid.
The same plot for Spokane airport suggests that eastern WA will have to wait an extra 12-18 hours before clearing commences.
And, none of the major models are suggesting a return to this ridging pattern within the next week. Meaning BC wildfire smoke is unlikely to blanket the state anytime soon. Just yet. We hope.
Wednesday, August 9, 2017
8/9/2017 Smoke Sense App reminder
This is a repeat of news that was posted last week on the blog about an App developed by the Environmental Protection Agency (EPA) for citizens affected by smoke from wildfires to see current air quality in their location, track their personal symptoms of smoke exposure, and get recommendations on ways they can protect themselves. EPA is testing the usefulness of the free App and you can help by participating in the trial. The App is only available at this time for Android phones. To learn more and to download the App go to: www.epa.gov/air-research/smoke-sense . Or you can get it directly from the Google Play store.
It's stuck until Friday at least
The high pressure system over us is a slowpoke. By the time is vacates our airspace this weekend, it would have calmly resided over us for about 10 days. It not only brought us a heatwave but also the flow conditions that helped transport copious amounts of BC wildfire smoke here. Some cheek, overstaying its welcome!
Last evening's satellite picture (~4PM) shows much of the state socked in with smoke. Apart from the movement of some high clouds, the animation looks almost identical to this image. In other words, the ridge is preventing any substantial air movement. Air quality degraded yesterday and prompted the reinstatement of burn bans in the Puget Sound region and the issuance of an air quality advisory in Southwest WA.
So the forecast is for more of the same on Wednesday and Thursday. Western WA will see air between Moderate and Unhealthy, with coastal areas showing Good air. Eastern WA will rarely improve beyond Unhealthy for Sensitive Groups.
Morning fog has been present close to water for a few days now (see background view in the Nisqually webcam) and should not be confused with smoke.
Though the ridge S-L-O-W-L-Y moves east of the Cascades on Friday, there is no strong intrusion of marine air to rapidly clear the smoke from western WA. While air quality will start improving by Friday evening, models suggest that it might be well into the weekend before on-shore winds are able gather enough steam to flush out the smoke (image below shows surface winds on Sunday morning). Eastern WA will take even longer to clear out.
Last evening's satellite picture (~4PM) shows much of the state socked in with smoke. Apart from the movement of some high clouds, the animation looks almost identical to this image. In other words, the ridge is preventing any substantial air movement. Air quality degraded yesterday and prompted the reinstatement of burn bans in the Puget Sound region and the issuance of an air quality advisory in Southwest WA.
So the forecast is for more of the same on Wednesday and Thursday. Western WA will see air between Moderate and Unhealthy, with coastal areas showing Good air. Eastern WA will rarely improve beyond Unhealthy for Sensitive Groups.
Morning fog has been present close to water for a few days now (see background view in the Nisqually webcam) and should not be confused with smoke.
Though the ridge S-L-O-W-L-Y moves east of the Cascades on Friday, there is no strong intrusion of marine air to rapidly clear the smoke from western WA. While air quality will start improving by Friday evening, models suggest that it might be well into the weekend before on-shore winds are able gather enough steam to flush out the smoke (image below shows surface winds on Sunday morning). Eastern WA will take even longer to clear out.
Tuesday, August 8, 2017
8/8/2017 Canadian fires still raging. No end in sight yet.
Fires in British Columbia are still active and showing very little sign of abating. As of today (Tuesday Aug. 8) there are 131 active fires in British Columbia. So far in 2017, 1,427,170 acres have burned in BC; their 10 year average acreage per year (2006-2016) is 382,875 acres so they are certainly experiencing a very extreme wildfire year and it's far from over. The six most significant and threatening of the BC fires are listed in the table below and the current perimeters of active fires in BC are shown on the map.
British Columbia Priority Wildfires
Name of Fire/Complex
|
Size (Ac.)
|
|
Elephant Hill (K20637)
|
284,171
|
About 115 miles north of US/Canada border above Ross Lake. About 85
miles W/NW of Kamloops; near Ashcroft. 30% contained.
|
West Quesnel Complex
|
197,684
|
About 275 miles north of the US/Canada border above Blaine, WA. 0%
contained. 109 firefighters, 11 helicopters, 22 heavy equipment. Evacuation
Order is in effect.
|
Central Cariboo Command
|
53,417
|
Fires from 0 to 40 % contained.
|
Hanceville Complex
|
64,741
|
|
Puntzi complex
|
25,451
|
|
Tautri Complex
|
258,719
|
A wildfire smoke dispersion model developed by the Canadians has been performing reasonably well to predict where the smoke from fires in Canada and the US will go. The modeled predictions for yesterday, today, and tomorrow at 5pm are shown below. Yesterday is shown for comparison so what you experienced in your location yesterday can be compared to the prediction for today and tomorrow. Many areas of Washington look pretty similar so no immediate change in the weather is expected to flush out the smoke. Remember this output is from a computer system that is trying to estimate fire size and growth plus meteorology so it will never be exactly correct. You can view the animations from the model at this link: https://weather.gc.ca/firework/firework_anim_e.html?type=em&utc=00
Déjà vu today and tomorrow. But not in comparison with previous years
Air quality degraded in western WA on Monday with the Puget Sound area experiencing Unhealthy air at times while the coast and southwest WA had Good to Moderate air. Tuesday and possibly Wednesday will be no different.
No Good air quality recorded anywhere in eastern WA yesterday, with most locations reading Unhealthy. And that will likely be the story for the next few days.
Déjà vu ends there. When compared to previous years, this wildfire season is unprecedented in the widespread nature of compromised air quality. Here's an animation of the worst days during the wildfires of 2012, 2015 and 2017, showing air quality conditions overlaid on a satellite map. Way more people were exposed to poor air this year than in the recent past.
However the percentage of time people breathed unhealthy air in 2017 is not as bad as past years, as shown by the barplot below. At least thus far. For instance, people in Spokane county were exposed to bad air about 5% of the time this year, while they had to deal with bad air for twice as long in 2015.
The # of acres burned, locations of fires and meteorological patterns all play roles in assessing public exposure to smoke. We will compile more data as it becomes available.
On an optimistic note, we're quite confident that the weekend will usher in a substantial shift in winds that will both cool the state and help dissipate smoke.
No Good air quality recorded anywhere in eastern WA yesterday, with most locations reading Unhealthy. And that will likely be the story for the next few days.
Déjà vu ends there. When compared to previous years, this wildfire season is unprecedented in the widespread nature of compromised air quality. Here's an animation of the worst days during the wildfires of 2012, 2015 and 2017, showing air quality conditions overlaid on a satellite map. Way more people were exposed to poor air this year than in the recent past.
However the percentage of time people breathed unhealthy air in 2017 is not as bad as past years, as shown by the barplot below. At least thus far. For instance, people in Spokane county were exposed to bad air about 5% of the time this year, while they had to deal with bad air for twice as long in 2015.
The # of acres burned, locations of fires and meteorological patterns all play roles in assessing public exposure to smoke. We will compile more data as it becomes available.
On an optimistic note, we're quite confident that the weekend will usher in a substantial shift in winds that will both cool the state and help dissipate smoke.
Monday, August 7, 2017
Monday and Tuesday will be like Sunday
For smoke that is, not because of an extended weekend.
The Canadian smoke model had it right yesterday- the inversion over western WA did break in the afternoon, mixing smoke to the Puget Sound lowlands. As winds died down, more smoke built up over the area. Sunset was more colorful than Friday and Saturday. Air was Moderate in most of western WA and Unhealthy for Sensitive Groups (USG) or worse in most of eastern WA.
The stark air quality divide across the Cascades persists. The air quality animation of the last few hours shows how areas west of the Cascades have improved compared to eastern WA, eastern OR and south central ID - which still have the ignoble distinction of having the worst air in the country.
Because it has been doing a reasonable job over the last few days, will
lean on the Canadian model for guidance. Expecting a repeat of yesterday
for both Monday and Tuesday: western WA mostly Moderate, eastern WA mostly USG; Very Unhealthy in areas closer to local fires.
The issue of large differences in pollution levels within a short distance has been raised. It seems reasonable that when smoke from a common source blankets a large area, concentrations should be fairly uniform. If large differences are observed, is it due to malfunctioning monitors?
Malfunctioning equipment is a concern and site operators work hard to ensure accurate and timely data delivery. However even in absence of localized sources, concentration gradients can arise due to differences in topography. Below is a comparison of two pairs of sites within ~15 miles of each other, showing very different levels this morning. The site at Neah Bay is at sea level and the site at Cheeka Peak is about 15 miles south and 1000ft above (difference annotated with a red curly brace). There are no major local sources nearby. The higher terrain is impacted by more smoke from aloft, and the low level inversion keeps Neah Bay somewhat shielded.
Similarly, the Tacoma area ventilated out early this morning but the smoke clung on in the Puyallup valley (annotated with a black curly brace), located about 12 miles east.
Moral of the story: there can be legitimate differences for sharp spatial gradients.
Finally, this graphic from the National Weather Service in Spokane has a succinct message for all of eastern WA:
The Canadian smoke model had it right yesterday- the inversion over western WA did break in the afternoon, mixing smoke to the Puget Sound lowlands. As winds died down, more smoke built up over the area. Sunset was more colorful than Friday and Saturday. Air was Moderate in most of western WA and Unhealthy for Sensitive Groups (USG) or worse in most of eastern WA.
The stark air quality divide across the Cascades persists. The air quality animation of the last few hours shows how areas west of the Cascades have improved compared to eastern WA, eastern OR and south central ID - which still have the ignoble distinction of having the worst air in the country.
The issue of large differences in pollution levels within a short distance has been raised. It seems reasonable that when smoke from a common source blankets a large area, concentrations should be fairly uniform. If large differences are observed, is it due to malfunctioning monitors?
Malfunctioning equipment is a concern and site operators work hard to ensure accurate and timely data delivery. However even in absence of localized sources, concentration gradients can arise due to differences in topography. Below is a comparison of two pairs of sites within ~15 miles of each other, showing very different levels this morning. The site at Neah Bay is at sea level and the site at Cheeka Peak is about 15 miles south and 1000ft above (difference annotated with a red curly brace). There are no major local sources nearby. The higher terrain is impacted by more smoke from aloft, and the low level inversion keeps Neah Bay somewhat shielded.
Similarly, the Tacoma area ventilated out early this morning but the smoke clung on in the Puyallup valley (annotated with a black curly brace), located about 12 miles east.
Moral of the story: there can be legitimate differences for sharp spatial gradients.
Finally, this graphic from the National Weather Service in Spokane has a succinct message for all of eastern WA:
Subscribe to:
Posts (Atom)