Tuesday, July 30, 2019

7/30/2019 Air Quality and Wildfires Update

So far this summer wildfire smoke impacts to air quality have been fairly minimal. Significant smoke from numerous large wildfires in Alaska and Canada barely brushed the state by traveling instead to the east and the Great Lakes region. But a few active wildfires burning in Washington are causing light smoke impacts in the south central portion of the state. The largest is the Left Hand fire burning to the west/northwest of Yakima. Winds have moved the smoke from this fire to the south/southeast and the town of Sunnyside has seen multiple days of Moderate air quality conditions due to smoke from Left Hand and from the Pipeline fire. Other nearby communities from Ellensburg to Toppenish, Naches, and Yakima have experienced light smoke at times and are likely to continue to see smoke until the Left Hand fire is brought under control. Air quality impacts from Moderate to short periods of Unhealthy for Sensitive Groups can be expected in this area. Somewhat windy conditions today (Tuesday) could cause the Left Hand fire to grow. The nearby Pipeline fire is at 95 % containment with minimal fire behavior so should not contribute to degraded air quality much longer. See map below for location of these fires.

Left Hand.  31 mi NW of Yakima, WA. Start 7/23. Full Suppression. Cause: Lightning. 2,500 (+0) acres. 15% containment. Active fire behavior. Timber. Structures Threatened. Road and Area closures.  More details here: https://inciweb.nwcg.gov/incident/6456/
Pipeline.  7 mi N of Selah, WA. Start 7/23. Full Suppression. Cause: Unknown. 6,515 (+0) acres. 95% containment. Minimal fire behavior. Brush. Area closures. Transfer of command back to local unit will occur today.

Location of Left Hand and Pipeline fires.
Another fire to watch over time is Devore Creek located in extremely rugged terrain high in the Glacier Peak wilderness near the north end of Lake Chelan. Firefighters on the scene in Stehekin report that air quality there has remained good. Due to the remote location and extreme terrain, firefighters expect this fire will not be 100 percent extinguished until a season ending rain or snow event in the fall. Some visible light smoke is possible at times around the north end of Lake Chelan, Stehekin, and Holden Village but unless fire conditions change, air quality is expected to remain Good.

Devore Creek.  3 mi SW of Stehekin, WA. Start 7/26. Confine/Point Zone Protection. Cause: Unknown. 150 (+0) acres. 0% containment. Timber. Trail closures. More details here: https://inciweb.nwcg.gov/incident/6463/
Location of Devore Creek fire.

Thursday, July 25, 2019

Smoke in Central Washington from Local Fires

Smoke plumes were visible this morning over Central Washington, and residents around Yakima are experiencing air quality in the Moderate to Unhealthy for Sensitive Groups range.  The smoke in Yakima will likely stick around for most of the day due to low winds and nearby fires.  Other residents in Central Washington that are near local fires could also experience some modest smoke.  

GOES-West Imagery (9 a.m. Thursday)

There was a lot of lightning earlier this week, and with it came new fire starts.  Fire fighters have been working hard to suppress and contain fires this week, with many put out quickly.  The NWCC Morning Brief  lists the remaining active fires that are not yet contained:
  • Kusshi Creek fire on the Yakama Indian Reservation: 320 acres (timber)
  • Left Hand Fire about 30 miles NW of Yakima (Okanogan-Wenatchee National Forest): 160 acres (timber)
  • Pipeline Fire between Yakima and Ellensburg: 4000 acres (brush)
  • Desert Canyon Fire about 15 miles NNE of Wenatchee near Lake Entiat: 1000 acres (grass).
  • Graham Fire about 10 miles SW of Cheney: 100 acres (timber)
  • Saddle Mountain Fire just north of Mattawa: 350 acres (grass)
Currently the fires are relatively small, but fire growth is expected as winds pick up over the next few days. Holdover fires are also likely to appear in the next several days. In general, fire behavior potential continues to slowly increase across the region.

Fires Detected by Satellite in Central Washington (July 25)

Temperatures will heat up and get drier today thru Friday, but it will be breezy Friday night into Saturday with a chance of thunderstorms in the Cascades. This will keep temperatures normal over the weekend but it will heat up again next week which will allow more fire growth.

Tuesday, July 9, 2019

Not much to worry about locally for now. Will this be a low-smoke summer?

Air quality remains Good statewide and will likely remain that way for the next few days. Some rain expected (< 0.5", but that's a lot for WA in July) and clouds are already streaming in, with temperatures running close to normal. Not great for summer but very good for air quality.

Here's how air quality looks nationally as of yesterday. Red triangles are fire locations and colored dots are air quality readings, the worst of which is "Unhealthy for Sensitive Groups". Smoke plumes are shaded gray.

The Great Lakes and Northeast is being impacted by smoke from fires in Manitoba & Ontario, while Alaskan smoke is what we're watching closer to home.

Here's what the fire danger assessment for north America is today. The bigger fires are mostly in Canada & Alaska thanks to very dry & hot conditions to our north.

What does this all mean for the rest of our summer? Are all those doom & gloom predictions of the "new normal" and smoke monsters laid to rest?

  1. Haha, I wish! Too early to tell.
  2. All it takes is two weeks of hot & dry conditions for the fire risk to ramp up significantly. 
  3. Even if (2) doesn't materialize, smoke transport from fires elsewhere can cause lots of air quality woes.
  4. And we won't know about (3) until a few days before the event, because longer range models aren't terribly accurate with those finer details.
So while enjoying the summer air, keep an eye on this blog. We'll do our best to keep you posted.

Friday, July 5, 2019

Weekend statewide forecast: some Alaskan smoke did add to the fireworks but should dissipate soon

How much damage did we do to our air yesterday?

Seems like we got through the 4th of July fireworks with no major, widespread degradation in air quality. North Bend and Marysville briefly recorded Unhealthy air last evening and several other sites are reporting Moderate air this morning. There is evidence that light amounts of Alaskan wildfire smoke did mix down to the surface today, as advertised by the Canadian smoke model. More on that below for anyone interested.

Weekend forecast

Expect Moderate air in splotches today as residual smoke clears out slowly during the day, and thereafter it should be mostly Good air statewide this weekend. There is nothing in the forecast over the next 5 days to suggest a major warm up or drying out. Temperatures around normal and slightly higher than normal precip all work against wildfires. We'll keep our focus on smoke transported from more distant sources.

About that Alaskan wildfire smoke theory

On Wednesday, the Canadian smoke model (also called "Firework", incidentally) was the only one which predicted Alaskan smoke will mix to the surface this morning. It was the most pessimistic of the suite of smoke models we use, but proved correct. How do we know that? Consider the following:

  • Timing of some of the increases in fine particle pollution levels: firework- induced (i.e. the loud, smoky and flashy ones, not complex software running on servers north of 49 degrees latitude) pollution typically spikes on the evening and night of July 4th and declines thereafter. Several sites in eastern WA show concentrations flatlining at Moderate levels into this morning without much of a decline. Sunnyside, Chelan and the Methow Valley in particular. 
  • Monitors in southern British Columbia, where fireworks aren't a factor on 7/4, also showed gradual increases this AM. While it is possible that some WA firework pollution may have been transported there (travel time of a few hours), the concentrations haven't declined like they did at our firework- smoke affected sites. Also, not all sites close to border crossings show evidence of a plume passing by late at night.
  • Satellite pictures this morning show a thin layer of smoke aloft and the above points suggest it did mix to the surface, albeit in small quantities.

Wednesday, July 3, 2019

Statewide forecast for Independence Day and beyond

Good news

Current air quality is Good statewide and there are no major fires at present. Atmospheric dispersion is expected to be somewhat OK through the weekend with temperatures, humidities and winds not given to rapid fire growth.

So... I can have a blast with fireworks, right? The atmosphere will self- clean, wont it?
Not so fast! A few things to consider:

  • Fireworks not only cause smoke but are also responsible for starting several new fires - something we can ill afford. This can't be over-stressed: as far as it depends on us, inject as little smoke as possible into the atmosphere and exercise utmost caution with pyrotechnics.
  • Dispersion is "somewhat OK", not fabulous. The self- cleaning cycle will only do so much for us, and we must not overwhelm it with preventable smoke.
  • Smoke from Alaskan fires is at our doorstep, or should I say rooftop, poised to gate crash the 4th of July party. Models are sending mixed messages whether or not some smoke will mix to the surface. The Canadian model suggests light amounts dropping down east of the Cascades.

The last thing we want to wake up to on the 5th of July is a dose of wildfire smoke AND firework smoke, especially when the latter is within our control.

Wishing our readers a happy & safe July 4th!  

Monday, July 1, 2019

Statewide Forecast - Good Air Quality in Washington

Alaska and Canada are still experiencing several wildfires and a lot of smoke.  We may see a wispy tongue of that smoke make it's way to the B.C./Washington border early Tuesday morning, but air quality should still remain Good over the next couple days

People will be testing out fireworks this week and typically we see more wildfires start around 4th of July due to human causes.  Please be extra cautious around dry grass/brush if you plan on celebrating with fireworks this week.  In particular, there are strong winds forecast in the Columbia Basin over the next couple days, and with it comes the possibility of brush fires.

National Weather Service - Spokane Office - Weather Story - June 1, 2019