I can provide definitive information about both smoke and rain.
As predicted by high-resolution models, the winds have turned easterly (from the east) over the Cascades, pushing smoke into western Washington and Oregon.
The visible satellite imagery this morning shows the smoky miasma over the region (below). You can see the smoke passing around the Olympics into the Pacific. Looks like smoke-free hiking near Snoqualmie Pass and on the eastern slopes of the Cascades.
The smoke has reached the surface around Puget Sound and southwest Washington. Red is poor quality and purple is even worse. The smoke is staying aloft as of this morning over the San Juans.
Here in Seattle, I can smell smoke outside and the Seattle PanoCam leaves no doubt (see below--at 12:30 PM)
All of this from a few minor fires.
The Northwest is the smoke capital of the U.S. today (see below), while California is nearly smoke-free.
I hate to say this, but Sunday will remain warm and smoky (high around 80F). But there will be cooling (into the upper 60s) next week and gradually reducing smoke.
Rain
The rain starting next weekend is a very sure thing. The American model has joined the European Center in dumping precipitation over the region. The ensembles of many forecasts are all on the same page.
Folks...a week from now, the warm, smoky summer will be over.... and perhaps some of you will miss it.
Let me show you.
Here is the 48-h rainfall totals ending 5 AM next Sunday. Wet in the mountains, but Puget Sound and the Willamette Valley will enjoy some rain shadowing.
This rain will end the local wildfire season. Temperatures will not climb above the 50s. You will be looking for hot cider and your sunglasses will have to be stowed away.
Today's temps are trending about 5 degrees below guidance, typical of smoky conditions with easterly flow. How come the models (or forecasters) can't or won't factor in the smoke cover when predicting high temperatures? I've seen this occur many times.
ReplyDeleteSimilar here in Bellingham. Expected an incredibly hot day based on the forecast, got a smoky morning and an average late August afternoon temperature-wise with smoke cleared out.
DeleteIt's as bad as a couple of years ago with the Oregon/B.C. smoke. Awful to be out in. Can't believe they are playing baseball and football here today.
ReplyDeleteCurious: presumably the air carrying the smoke to us is the same air that passed over the fires and fed the flames. The smoke is a sort of "tracer". So is that air measurably depleted of O2, and enriched in CO2??
ReplyDeleteNope. The weight of smoke particles is insignificant. A cubic meter of air would only contain milligrams of smoke, with corresponding decrease in O2.
DeleteI did not ask about the weight of the smoke - and as the plume is maybe kilometers long and kilometers wide, a single vertical meter across the length and width of the plume would contain some millions of cubic meters of particles and thus thousands of grams (kilograms) of smoke. Increase the thickness of that horizontal slice, and you have at least hundreds of kilograms of smoke.
DeleteLow densities do not mean low totals. A forest has literally gone up in smoke. Its mass has not changed.
The smoke concentration is low, but it is easily(!) detected, and almost as easily measured. So too are the concentrations of CO2 and O2, and they can be measured to probably better than 1 ppm (not so easily though). What are those concentrations, and how do they compare to the air just upwind of the fire?
This is such an interesting question. I'd love to know, too.
DeleteThe only quantitative info I could find were journal articles about the validation of models. Way too much information. It seems to be the CO that's impacted much more than co2. Inefficient combustion, probably. Also a lot of toxic products of combustion. It still has to be the case that O2 is depleted.
DeleteSo, we have another week of toxic air quality before next weekend's rain? And all this due to a "few minor fires". LOL
ReplyDeleteThey're minor in terms of size. Even small fires can create lot of smoke. This smoke event is historic for its duration, as it started in early September and has not abated much despite minimal growth of the fired since then
Deletesmall smoldering fires can produce localized smoke....and the Bolt Creek fire has been a smoker. Fortunately, this event ends this weekend.
DeleteLast time I checked, Bolt was 13k acres and 30% contained. That might be minor compared to other larger fires caused by climate change, but is still quite large for PNW standards.
DeleteWith a high pressure lid over the top of us even minor fires create enough smoke to cause significant grief. A few years back the USFS started a very small prescribed Fall burn in our area, unfortunately high pressure moved in and the resulting inversion trapped thick smoke for days near the surface. The smoke producing fire was maybe 1/2 an acre!
ReplyDeleteI would not call these "minor fires",especially the ones located in the forest areas on the west slopes of the Cascades. They may not be like the multi-thousand acre fires that have burned in eastern Washington in recent years but many of those acres were grass or scant timber lands. It has been many years since there have been this number of fairly large heavy timber fires on the west side of the Cascades and these produce lots of smoke.
ReplyDeletethese are small fires in terms of acreage. There have been recent large west-side fires...the Sept 2020 fires on the western side of the Cascades dwarfed these. Also consider the recent Eagle Creek fire near the Gorge.
DeleteWestern Oregon had large acreage fires in 2020 and the Eagle Cr. fire earlier. I am referring to western Washington where you would have to go back many years to find this many fires burning this much acreage.
DeleteI don't think the atmosphere knows about the state boundary. And Eagle Creek did jump the Columbia.
DeleteWhile it's good that this wildfire season has involved less acreage, etc - I was dismayed to hear DNR's Franz say that the agency's plan was to let the Bolt Creek fire "burn out." When I was first here in the PNW in the 70's, the Forest Service (USFS) had fulltime fire crews, and the forests were definitely being logged - managed - more, and there were fewer summer fires, air quality was better.
ReplyDeleteI've been wondering - how much CO2 do wildfires and forest fires cough-out? Just curious.
In Tacoma, definitely seeing some smoke here, but clearly not as bad as Seattle and I'm ready for the fall rains to come. Got to enjoy the nice weather last Sunday with a trip to Mt Rainier for a picnic with several family members as that was the last day of Cougar Rock to be open for the season as it's above the snow line, and it can come along near the end of October and then you will need a 4x4 to reach that area and on up to Paradise. We went into the park through Longmire.
ReplyDelete