A taste of Fall weather will arrive this week.  Remember to roll up the car windows.

 

The leading edge of a cooler air mass will begin to arrive from the NW as early as Tue evening over Vancouver Island.  This portion is not particularly wet, so we must wait a bit longer for steady rain.  That said, don’t rule out a few showers possible over NW WA by Wed, esp higher elevations.  It will continue to 

cool down across the entire PNW on Thu the 16th.  

 

By Thu night, expect the rain field to arrive, draping across the region from north to south.  Fri looks WET & breezy.   Chilly air will pool over the PNW as a Low slowly moves in on Sat.  Expect on/off showers through the weekend; sweaters or coats will be come out of the closet.  The cold front will move over ID by late Sunday.  A crisp morning will greet the new work/school week on the 20th.  Fall colors will be triggered.

 

Models have been trending away from another large system on Wed the 23, but not completely.  If the system does develop, most of the precip should fall north of Portland or be limited to NW WA.  Generally, without that system, mild & sunny afternoons (lots of 70s) should prevail much of that week.  The weekend of Sep 25,26 may turn wet again, esp for the northern half of WA and BC.  Oregon & Idaho could remain mostly dry.  

 

In the Sep 25-29 period, model solutions keep the ‘jet-stream’ upper-level winds rushing over southern BC, holding most of the rain up in southern BC, clipping Vancouver Is & the far NW corner of WA.  Breezy at times, though, for much of the PNW.  Rain may return by Friday Oct 1st.

 

Bottom line: we are finally on track for measurable rainfall.  The uncertainty for rain beyond this Friday’s (& weekend) storm centers on how far south the ‘jet stream’ will shift afterward, resulting in additional rain for all of the PNW.  To repeat, latest trend is leaning toward Canada, not OR, WA, ID. 

 

Personal Note:  the Giant Pumpkin Project here in the retirement community has been a success.  Final Weight Estimate will be Tue Sep 14.  The image of “The Pumpkinator” (below) was taken Saturday evening (we’ll share the weight in the next report.)

 

Repeat from the past: “Some tasks have to be put off dozens of times before they completely slip our minds.”

 

 

A difficult day of Remembrance tomorrow, Nine-Eleven.  We will never forget.  

 

The wx pattern charting for the next couple of weeks remains on track with our last discussion.  We are trending favorably to receive the first notable rainfall around the region since last June.  There is a band of moderate moisture moving to the NE along the east of the Cascades this morning, hence some cloudiness west side, as an upper-level Low spins on by.  This weekend continues to trend generally dry & mild.

 

The pattern shift due to arrive late next week is positive for the sound of rain drops.  The key change since our last update is that the 1st round of rain may arrive as early as next Fri, Sep 17.  If not that soon, at least the models KEEP the wet system as a ‘go’ for arrival sometime the weekend of Sep 18,19.  Breezy & cool conditions along with the precipitation.  Ah, the feel of fall.  

 

As the week of Sep 20 begins, there are two options on the charts: 1) expect a short dry period before the next fall rain arrives either mid-week with more again the following weekend or, 2) damp on/off through the first half of the week, then drying over the weekend of Sep 25,26.  WINDY at times, either way.  Which option verifies all depends on just where the center of the large trough of Low pressure sets up in the Gulf of Alaska.  We have time to firm up the forecast beforehand.

 

Again, models vary the timing of, but not the possibility for, rain.  In between the storms, temps will warm nicely over OR, while remaining rather cool for Puget Sound Patrons.  (Patrons on Vancouver Island, in SW BC and maybe the far NW corner of WA, are likely to receive large amount of rainfall throughout the second half of September.)  As noted, WIND will be a factor at times, mainly east side.

 

The week of Sep 27 is trending on the wet side, overall.  Fall.  

 

 

 

The holiday weekend that traditionally shifts us from summer to fall is just about over.  Our Patrons are fully aware of the variability in long-range forecast models, hence, it remains a morn’n tradition (since 1994 for some of you) to sip a morn’n bev from that special Mug to ponder the various weather patterns that may develop in the weeks ahead.  Thanks for reading The Weather Café ®️.

 

Broadly speaking, there may be a shuffle in the atmosphere sometime mid-month.  That shuffle could FINALLY introduce the possibility of notable precipitation across the PNW.  Will it happen?  For now, expect dry and on/off WINDY conditions to prevail through approx. Fri Sep 17.  By Thu this week, temperatures will cool down a few degrees, as the onshore flow picks up.  Breezy afternoons.  Nine-Eleven looks dry, pleasant.  Warmer & breezy on Sunday Sep 12.  Good sailing in the Sound? 

 

The week of Sep 13-17 charts as starting out WARM.  A ridge of High pressure will be positioned to bring on a couple rather WARM afternoons.  Upper 80s to lower 90s possible, esp in OR.  By mid-week, the early stage of that “shuffle” may begin, with cooler onshore flow increasing notably because a trough digs southward from the Alaskan panhandle, coast of BC.  NW winds, which could be strong east of the Cascades.  Concurrently, High pressure over the interior of Canada may begin moving south, east of the Rocky Mtns.  

 

Last week, we were looking at that same High movement to be centered farther west, setting up very windy conditions for portions of the PNW.  Model runs have shifted that threat, and in doing so, opens the door for Low pressure to move in from the NW - meaning RAIN possible in the Sep 18 - 20 period.  Not a promise, just a ponder point for now.  It will be WINDY CITY for northern tier states of the US heartland.  This whole outlook is variable, depending on where that High pressure is centered.  The pressure gradient will be from west to east, therefore, a strong east wind event is NOT probable.  

 

As you can tell, model solutions vary considerably for our weather during the Sep 16-20 period, with solutions ranging from dry, warm to windy, cool & damp.  Since the later solution has charted the most, it warrants our mention here as possible.  Sip & Ponder.  

 

 

 

New month and the beginning of the “meteorological fall” season.  Is precipitation on the way?  Fill your Mug before reading the answer.  

 

Labor Day Weekend:  a cooler, showery pattern arrives on Saturday, mainly over western WA & southern BC.  Sunday will be a transition day back to WARM sunshine on Labor Day.  Warm, dry conditions will continue through Tue, with Wed ushering in the possibility for thundershowers over portions of the Cascades (OR, primarily).  Mild conditions Thu & Fri, with wind late in the period.

 

As the following weekend (Sept 11,12) approaches, another weak system may drop in from the NW, so expect clouds to increase with the chance for showers - this time over a larger area of the PNW - as that Low spins over N Vancouver Island by Nine-Eleven.  << we will never forget >>   Not a washout, just the chance for wet pavement, at times.  That written, please note, there are solutions that keep the Low farther offshore as it drops south, ushering in a muggy, thunderstorm-type pattern, with WARM temps, esp for OR & eastern basins.  The wind mentioned below may start early.  Read on.

 

A cautionary tale. The middle week of September is trending on the windy side — with a relatively strong Low moving down the coast of BC, setting up possible showers early in the week, or even steady rain over NW WA, then WINDY conditions for OR as that week nears an end.  Actually, a notable ridge of High pressure may begin building over the Yukon and drop south, with WINDS really picking up for much of the PNW by Thu night or Fri.  Pattern could mean WIND trouble for fire concerns in OR, CA & ID.  Pressure gradients are charting in the “oh my” category, if verified, for Fri Sep 17.  Let’s hope for model error.

 

Temperatures will warm again as that air mass compresses and heads for the coast.  Warm conditions (upper 80s OR, bit cooler for the Sound) Sunday Sep 19 that may hold into the middle of the next week.  Gusty NE winds in western valleys.  Quite stormy over the US Midwest, as that 9-11 system mentioned above rolls out of the Rocky Mountain states to stir up a windy, wet mess.  And, oh, there could be a tropical storm playing games with us in the Gulf of Mexico.  Yikes.

 

Bottom line: the PNW may actually get into a brief period when showers & some rain arrives.  At least there’s a higher chance than what we have seen since last June.  The wind concern will not be like last year, but definitely a potential that would not be good for firefighters.

 

Update on The 2021 Walk to End Alzheimer’s - Sept 25.  Our WxCafé Patrons are simply awesome!  With 3 weeks to go, over $2,700 has been contributed to this important cause.  THANK YOU!  Every donation makes a difference, no matter the amount.  We will update again next Fri. 

 https://act.alz.org/site/TR?fr_id=14724&pg=personal&px=18670512

 

 

 

 

Warm summer days will return.  When?  Mug refill time to find out.

 

A cool air mass moved down the BC coast to usher in notably cooler temps in the PNW.  This week will remain cool early, then warm up a bit on Wed & Thu.  But the warmth will not last long.  Looks like the model solutions that forecast a cool, damp holiday weekend (for BC & NW WA) may be the most accurate. 

 

Right now, expect clouds to increase from the north early on Fri Sep 3, setting up a partly cloudy day on Sat of the holiday weekend.   Portions of OR & east side should remain sunny.  Isolated showers possible for the Puget Sound (maybe as far south as Longview/Kelso) both sometime Sat and even more likely on Sunday Sep 5.  While a bit breezy, Labor Day itself should turn clear and DRY.  Portions of western OR, and east, will likely warm into the lower 80s again.  

 

Summer days return.  Tue & Wed after Labor Day are trending WARM and DRY.  Temps could tease the lower 90s in portions of western OR.  Onshore flow may increase by that weekend, holding down temps.  The upper air flow may turn SW, which will pop up humidity and slowly build in the chance for thunderstorms and moisture across OR.  This is way out there, but model solutions are beginning to find this solution.  Temperatures should remain mild-to-warm.

 

Really?  There are indications that mid-September may turn damp.  Not strong-pacific-storm-damp, but enough of a pattern change to bring much needed precipitation across the region.  Firefighters long for this.  We all long for this.