Cool Air is Starting to Move In

Today broke several daily temperature records,  with temperature climbing into the mid nineties around Seattle and upper 90s to the east.  The interior of SW WA and the Portland area jumped to 100F and more, as did the Tri-Cities.

Here in Seattle, temperature were quite pleasant on Puget Sound, but jumped into the mid-90s over NE Seattle.   Even hotter over Bellevue and Redmond.

But as forecast, everything is changing now.  The trough of low pressure (the thermal trough) has jumped over the Cascades and an onshore pressure gradient has developed (see pressure difference table below). The Hoquiam minus Seattle pressure difference jumped to 3.5 hPa...guaranteeing the inland movement of cool air.

The winds  and temperatures above Seattle Tacoma Airport show the incipient changes,  with hot SE winds replaced by cooling southwesterlies aloft.  And temperatures aloft are falling.

Coastal clouds have moving northward and thickening during the day (see satellite image from an hour ago) and those clouds will move in overnight.

I look forward to hearing the tinkling of my wind chimes around midnight, a sign of the influx of welcome marine air.  Our regional AC has been turned on....now it is only a matter of time.

from Cliff Mass Weather and Climate Blog http://ift.tt/2taVUvF