Updated Friday 5:15 p.m.
TGIF! What a beautiful way to wrap up the work week. Our cool onshore flow from the coast continued today, and all of that oceanic goodness continued working on the clean up of our air quality. The lower reaches of the atmosphere are nearly back to decent: air quality sensors registered as "good" to "moderate" from the ocean beaches to the Cascade foothills on Friday afternoon. The seabreeze also served to keep us cool. Daily temperatures maxed out only in the 60s and the 70s around the Sound--readings that definitely felt cool compared to the 80s that dominated much of the month of August so far.
But if you're not ready to say goodbye to summer warmth, don't despair. We'll head right back into some heat this weekend, with highs building closer to 80 near the metro area on Saturday, and low to middle 80s on Sunday. The sunshine and warm temperatures will be perfect for enjoying the Chalk Art festival in Redmond or the beer fests in Tumwater or Seattle.
However, the building heat will mean a changing wind direction again. The west winds that brought the refreshing ocean breeze will turn off, replaced by north winds as the weekend goes on. There are still numerous fires burning in British Columbia, and some of that smoke will most certainly work its way back into Puget Sound by Sunday and Monday. We'll hope that the air quality doesn't get as bad as it did a few days ago, but prepare for it to deteriorate again to some degree.
While a change in wind direction is helpful, we really need a good round of RAIN to wash away the smoke. And it looks like we may finally get some by late Monday and Tuesday. However, it may come with a price...
Temperatures build into the middle to upper 80s on Monday thanks to the influence of the warm north winds. With that warm air mass already in place, a little trough of low pressure--a.k.a. a "disturbance"--rides on into Western Washington late Monday. The warm air underneath will help trigger some instability, so any showers that develop may start to include thunder and lightning, too. While we certainly want the rain to wash out the smoke and ease the fire danger, any lightning could pose a bigger threat for starting more wildfires. In other words, the lightning may be more harmful than any rain will be helpful.
We'll keep on top of that scenario as we get closer, but in the meantime, enjoy this pretty summer weekend (and cleaner air, too!).
Have a great night,
Meteorologist Shannon O'Donnell
The KOMO4 Forecast Team
Today's Record Temperatures