Another Surge Of Wildfire Smoke Hits Puget Sound: The Worst On Record

Folks were surprised how speedily the air character deteriorated sun afternoon, rapidly going from moderate air character to unhealthy weather amongst a profound loss of visibility.     Things improved over nighttime only about Seattle, but thence went downhill today--with the worst hourly fume levels on tape (back several decades).

Let me demo yous in addition to explicate the fascinating in addition to complex province of affairs nosotros are in.

Here is a plot of the particulate levels (PM2.5) at the Puget Sound Clean Air Agency Duwamish site from terminal Tuesday to three PM today (Monday).   You tin encounter the rapid surge of fume yesterday afternoon, followed yesteryear a precipitous autumn inwards yesterday evening.  And thence it started rising 1 time again this morning, reaching a peak at nowadays that is far higher that either yesterday or terminal week.

In fact, this hourly fume aeroplane is the highest on tape at this site (going dorsum roughly ii decades) and higher than anything terminal summer--the plot below is the proof!

Yesterday, equally the winds aloft turned northerly in addition to northeasterly, the huge reservoir of fume inwards British Columbia in addition to eastern Washington surged southward overhead, but air character did non spend upwardly immediately.

As the surface warmed, the lower atmosphere started to mix, higher in addition to higher, eventually tapping the fume aloft in addition to bringing it downwardly to the surface.  That is what caused the air character to rapidly degrade.

Last night, the surface cooled,  the mixing driven yesteryear surface heating dropped off, in addition to the lower atmosphere became stable, amongst trivial vertical mixing.  So nosotros stopped tapping the fume aloft.   Then relatively construct clean air moved into key in addition to northern Puget Sound from the Strait of Juan de Fuca, leaving us amongst improve character air, which was acquaint this AM.

But why did things larn thence bad this afternoon?   For 1 thing, the surface started to warm, resulting inwards to a greater extent than mixing of fume downwardly to the surface.   The noon MODIS satellite imagery clearly showed fume higher upwardly the portion in addition to peculiarly Puget Sound.  Eastern WA looks similar something out of Dante's Inferno.

But await actually closely.  You tin encounter fume plumes over the eastern slopes of the North Cascades, amongst the fume moving toward Puget Sound.

The 3:40 PM satellite icon from the NOAA GOES satellite shosw the fume from these fires crossing the Cascades in addition to reaching Puget Sound. Some domestic smoke.  H5N1 source of primo fume aloft.

As illustrated yesteryear the EPA AirNow graphic, although it is smoky over Puget Sound, it is crazy bad inwards Port Townsend in addition to Port Angeles, too equally areas along the eastern slopes of the North Cascades where the numbers are inwards the 200s.   Extraordinarily unhealthy.

What most the future?   Let's depository fiscal establishment tally out the NOAA HRRR fume forecasts, which pick out proven to endure stunningly good. Tomorrow, the winds choke increasingly easterly, which agency eastern WA fume volition endure coming correct into us (see forecast for three PM tomorrow).  Not much improve than today.

Midweek is the transition day, amongst a onshore, marine force start that evening.  Thursday, should endure a MUCH improve day, amongst construct clean body of body of water air over our region.

On a lighter note, the Puget Sound Clean Air Agency gives advice on what yous should create inwards this smoky situation.  The entirely matter advisable is to run on your laptop!