Hottest day of the year (so far) likely tomorrow

Aug 3, 2012

Sometimes, like this weekend ... a miracle happens, reports our weather expert and University of Washington professor Cliff Mass. 

That miracle may bring the hottest day of the year this weekend.

Mass explains in his blog:

A lobe of high pressure extends inland of us, forcing offshore flow. This offshore (easterly) flow starts over the heated interior of the continent and then gets even warmer when it sinks down the western slopes of the Cascades. The result is that a tongue of warm air extends northwestward out of the southwest – generally northward from the interior valley of California or the intermountain West – towards our region.  

Thermal troughs not only bring warmth. Often the heat results in poor air quality (high ozone), and thermal trough passage over the mountains can really rev up any wildfires that are smoldering. Thermal trough passage causes big wind shifts that can play havoc with wind energy predictions.  You can see why we are studying these troughs...they are important for a number of reasons!