November 2019 Weather Discussion for the PNW

[Gradient Keeper]

18z GFS Ensembles bit colder. Yakima ensembles shows bit better signal for backdoor cold. Hmmm!

 

00z GFS in 3 hours 26 minutes

 

Portland

http://old.wetterzentrale.de/pics/MT8_Portland_Oregon_USA_ens.png

 

 

Seattle

http://old.wetterzentrale.de/pics/MT8_Seattle_USA_ens.png

 

 

Yakima

http://old.wetterzentrale.de/pics/MT8_Yakima_USA_ens.png

[SilverFallsAndrew]

Definitely some hope for the long range. Going to be pretty mild for the next 10 days though. WOW.

[MossMan]

Looks like quite the CZ going on in the Everett area currently!

[Blizzard777]

Lots to like if you like blocking with the 12z model suite today. 12z ensemble runs agree with the block retrograding as well.

 

Plenty of cold potential beginning Thanksgiving week headed into December it would seem.

Brother down in PDX just tex me that freezing rain/ rain just showed up in forecast for the 29th 

East winds I assume

[TT-SEA]

Looks like quite the CZ going on in the Everett area currently!

I checked some web cams... air looks cleaner.

 

Yesterday looked pretty disgusting.

[Brian_in_Leavenworth]

It's been awhile. Dry though.

 

 

Some interesting years, particularly 2008.

 

[TacomaWaWx]

I checked some web cams... air looks cleaner.

Yesterday looked pretty disgusting.

Yes, you can see how smoggy the air was in the lower levels from the top of bearhead yesterday. Southerlies and rain have the air smelling fresh again.

[TacomaWaWx]

56/46 today, this was the warmest day of the month here locally and the warmest day since 10/25. After getting a quarter inch of rain this morning the sun came out and it was a really nice day.

[seattleweatherguy]

Looks like quite the CZ going on in the Everett area currently!

Thunderstorms or just heavy rain? 

[seattleweatherguy]

Heard a rumble but its long gone now maybe the cz zone isnt moving south

[Gradient Keeper]

...SPECIAL WEATHER STATEMENT...At 522 PM PST, Doppler radar was tracking a strong convergence zone extending from near Index to Mountlake Terrace. Movement was southeast at 30 mph.Lightning, small hail, brief gusty winds, and minor street flooding will be possible within the convergence zone. Expect disruptions to the evening commute.Locations impacted include...Seattle, Everett, Edmonds, Gold Bar, Index, Redmond, Kirkland,Lynnwood, Bothell, Mountlake Terrace, Mill Creek, Monroe,Woodinville, Duvall, Sultan, Woods Creek, Shoreline, Kenmore, LakeForest Park and Brier.

[Gradient Keeper]

ECMWF Weeklies

Week 2: November 25th - December 2nd

Rooting as hard as I possibly can for Cluster #4! Only an 8% probability, but ya never know! That "something" tripping up the models I suspect has to be the SSW event. Think Cold and SNOW!!!! C'MON!!!!

 

Michael Ventrice‏

Per our ECMWF Weekly Model Scenarios via http://wsitrader.com sub-seasonal, It's not typical to see this much variance in the ECMWF Weekly Model for Week 2. Something is tripping the model up. For Week 3 on the other hand...

 

[Gradient Keeper]

...SPECIAL WEATHER STATEMENT...At 522 PM PST, Doppler radar was tracking a strong convergence zone extending from near Index to Mountlake Terrace. Movement was southeast at 30 mph.Lightning, small hail, brief gusty winds, and minor street flooding will be possible within the convergence zone. Expect disruptions to the evening commute.Locations impacted include...Seattle, Everett, Edmonds, Gold Bar, Index, Redmond, Kirkland,Lynnwood, Bothell, Mountlake Terrace, Mill Creek, Monroe,Woodinville, Duvall, Sultan, Woods Creek, Shoreline, Kenmore, LakeForest Park and Brier.

 

UPDATE ...SPECIAL WEATHER STATEMENT...At 548 PM PST, Doppler radar was tracking strong thunderstorms alonga line extending from near Index to near Bothell. Movement wassoutheast at 25 mph.Lightning, small hail, brief gusty winds, and heavy rainfall/minor street flooding will be possible within the convergence zone. Expect disruptions to the evening commute.Locations impacted include...Gold Bar, Carnation, Index, Redmond, Sammamish, Bothell, Woodinville,Duvall, Skykomish, Baring, Pine Lake, Echo Lake, Sahalee, May Creek,Union Hill-Novelty Hill, Cottage Lake, Kingsgate, LakeMarcel-Stillwater, Maltby and Startup.

[Gradient Keeper]

5:52 PM Radar Update

 

[TacomaWaWx]

5:52 PM Radar Update

 

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pretty nice CZ too bad it never comes down south to Tacoma really :/.

[snow_wizard]

Definitely some hope for the long range. Going to be pretty mild for the next 10 days though. WOW.

 

We actually have a trough digging from the NW early next week.  That should get things chilly again.

[snow_wizard]

If we do end up with a cold snap to finish out the month like some GFS runs and ensemble members are showing that would make this late Oct through Nov period a dead ringer for 1936.  Fun to contemplate.

[snow_wizard]

The small block for early next week has actually trended pretty favorably for us.  Certainly enough to bring the chill back.

 

 

[snow_wizard]

5:52 PM Radar Update

 

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I saw a lightning flash from that on my way home from work today.  It's like every time we get significant precip this fall we get lightning at some point.

[seattleweatherguy]

 

UPDATE 

...SPECIAL WEATHER STATEMENT...

At 548 PM PST, Doppler radar was tracking strong thunderstorms along
a line extending from near Index to near Bothell. Movement was
southeast at 25 mph.

Lightning, small hail, brief gusty winds, and heavy rainfall/minor 
street flooding will be possible within the convergence zone. Expect 
disruptions to the evening commute.

Locations impacted include...
Gold Bar, Carnation, Index, Redmond, Sammamish, Bothell, Woodinville,
Duvall, Skykomish, Baring, Pine Lake, Echo Lake, Sahalee, May Creek,
Union Hill-Novelty Hill, Cottage Lake, Kingsgate, Lake
Marcel-Stillwater, Maltby and Startup.

Dang hear the rain now

[jcmcgaffey]

Well over an inch for places up north of seattle from that convergence. Some places approaching two inches.

[snow_wizard]

Well over an inch for places up north of seattle from that convergence. Some places approaching two inches.

 

For that to happen within such a dry context is quite unusual.  We have seen this a few times this season.

[snow_wizard]

Here is my prediction for the next couple of weeks.  First the trough early next week will be enough to get our frosty nights back.  From there the entire dry period following should be on the chilly side due to inversions and northerly surface pressure gradients  After that (8 to 11 day period) we will see the blocking retrograde, but still be too far east to be all that exciting for us.  About 4 to 6 days later there will be another retrogression step that will bring us something notably chilly in early December.

 

That's the way things look at this moment at least.  It's still possible the retrogression around day 10 could nail us with cold, but I think we will have to wait until the next step.

[BLI snowman]

If we do end up with a cold snap to finish out the month like some GFS runs and ensemble members are showing that would make this late Oct through Nov period a dead ringer for 1936.  Fun to contemplate.

 

Lots of similarities with 1976 and 1952 as well, though. Both of those Novembers ended cold for us.

[SilverFallsAndrew]

My flight from Spokane was diverted south into Sea Tac to avoid the t-storm. 

[snow_wizard]

Lots of similarities with 1976 and 1952 as well, though. Both of those Novembers ended cold for us.

 

Those two years had very warm Octobers though.  1936 was also a pretty warm October, but had the cold finish.

[Deweydog]

Drizzle!

[MossMan]

My flight from Spokane was diverted south into Sea Tac to avoid the t-storm.

Were you flying into Everett?

[TigerWoodsLibido]

We actually have a trough digging from the NW early next week.  That should get things chilly again.

 

The 540 thickness line finally crosses again!

[Cloud]

I checked some web cams... air looks cleaner.

 

Yesterday looked pretty disgusting.

The rain this morning was definitely needed. It hasn’t been discussed much, but the air quality was stuck in “moderate” for a good week, week and half.

[TT-SEA]

The rain this morning was definitely needed. It hasn’t been discussed much, but the air quality was stuck in “moderate” for a good week, week and half.

 

 

I saw the bad air quality... I know it was pretty gross.    

 

But technically... just a switch to SW flow would clear it out.   The amount of rain was pretty much meaningless to that process.    And our water supply will be determined by mountain snow this winter and next spring... not rainfall in Seattle.

[Cloud]

I saw the bad air quality... I know it was pretty gross.

 

But technically... just a switch to SW flow would clear it out. The amount of rain was pretty much meaningless to that process. And our water supply will be determined by mountain snow this winter and next spring... not rainfall in Seattle.

This is why after the rain, I prefer some wind to stir up the air to clean out the nasty stuff. That hasn’t been the case. Even after the front moved through this morning, it got windy so that was the main factor in cleaning out the air.

 

I’ll take that any day if it’s not gonna rain.

 

Also, the one thing that surprises me the most with the current pattern is we don’t see much inversion. Typically this time of year, if it doesn’t rain we’d be socked in with a nasty inversion with fog capable lasting whole day.

[TT-SEA]

This is why after the rain, I prefer some wind to stir up the air to clean out the nasty stuff. That hasn’t been the case. Even after the front moved through this morning, it got windy so that was the main factor in cleaning out the air.

 

I’ll take that any day if it’s not gonna rain.

 

Also, the one thing that surprises me the most with the current pattern is we don’t see much inversion. Typically this time of year, if it doesn’t rain we’d be socked in with a nasty inversion with fog capable lasting whole day.

 

 

Yeah... I was thinking the same thing about the lack of all-day fog.   Might be just a little early though... maybe late November through late January for the true heart of the inversion season?

[Gradient Keeper]

Looks like enough cold air filters south that we may see a Columbia Basin cold pool next week. Hmmm! C'MON!!!!

 

00z GEFS in 24 minutes

[Gradient Keeper]

Yep 850s Day 4.5 to 10 definite modest cold pool coming. Not overly strong or impressive, yet.

[TT-SEA]

Based on the 00Z GFS... I am guessing some bad air quality will be coming back eventually.

[TacomaWaWx]

Based on the 00Z GFS... I am guessing some bad air quality will be coming back eventually.

seems like we’ve had a good amount of inversionish days already before the main inversion season even started.

[ShawniganLake]

0z GFS was poor. Ensemble not much better.

[Gradient Keeper]

00z GEFS no retrogression through Day 13.... Well that's not what we were hoping for.

[Gradient Keeper]

Onto King EURO in 17 minutes