PNW November 2021 Wx Obs/Discussion

[Anti Marine Layer]

Just now, Deweydog said:

No.

Then why would the cooling system come on?

[Gradient Keeper]

7 minutes ago, Deweydog said:

Latest 66 degree day at PDX since 11/14/01 when they hit 67.

[Anti Marine Layer]

3 minutes ago, The Swamp said:

Just hit 65 here in The Swamp.

This is a good sign for cold winter weather.

Pineapple Express. 

[Gradient Keeper]

7 minutes ago, Brian_in_Leavenworth said:

If it was cold and snowy, people would be saying that it dooms us for the rest of the winter.

Haha, yep! Without fail.

00z ECMWF in 8 hours 44 minutes

[snow_wizard]

37 minutes ago, MossMan said:

My friend that lives at Lake Chelan just posted on FB saying she is sitting on her deck in 70 degree sunshine…Sounds lovely!

Definitely comforting seeing this in November.

[snow_wizard]

Not exactly what I was expecting today.  More wind and a lot less rain.  The Central and North Cascades are still getting pounded though.  SEA just had a gust to 43.  They have had a lot of wind lately.

[Phil]

4 hours ago, snow_wizard said:

And even if the East does score some major cold in November....so what?

The West and East can both score (at different times or simultaneously) in the same without it being to the detriment of the other.

There is a rich history of it. Even recently. 2020/21, 2018/19, 2013/14, 2010/11, 2008/09, 2003/04, 1995/96, 1985/86, etc.

Doesn’t happen 100% of the time, but I never understood why it is viewed as a mutually exclusive endeavor. If anything, extremes beget extremes. On average, +EPO increased the chance of a blowtorch for both the West and the East, and vice versa for -EPO. 

[T-Town]

Sounds like we may wrap this thing up with a destructive windstorm. 
 

 

[snow_wizard]

12 minutes ago, Brian_in_Leavenworth said:

If it was cold and snowy, people would be saying that it dooms us for the rest of the winter.

Cold Novembers are usually the kiss of death for January, but Dec and Feb are still very much in play with that.

[snow_wizard]

3 minutes ago, Phil said:

The West and East can both score (at different times or simultaneously) in the same without it being to the detriment of the other.

There is a rich history of it. Even recently. 2020/21, 2018/19, 2013/14, 2010/11, 2008/09, 2003/04, 1995/96, 1985/86, etc.

Doesn’t happen 100% of the time, but I never understood why it is viewed as a mutually exclusive endeavor. If anything, extremes beget extremes. On average, +EPO increased the chance of a blowtorch for both the West and the East, and vice versa for -EPO. 

Totally agreed.

[snow_wizard]

4 minutes ago, T-Town said:

Sounds like we may wrap this thing up with a destructive windstorm. 
 

 

This isn't a bomb situation.

[Gradient Keeper]

4 minutes ago, T-Town said:

Sounds like we may wrap this thing up with a destructive windstorm. 
 

 

Yeah the latest HRRR and even NAM 3km paint the same picture.

[Gradient Keeper]

1 minute ago, snow_wizard said:

This isn't a bomb situation.

No, but the low is intensifying as it moves onshore and even increased cyclogenesis as it moves towards Alberta.

[T-Town]

4 minutes ago, snow_wizard said:

This isn't a bomb situation.

Whatever the underlying cause there are big numbers on those maps. 

[TT-SEA]

Up to 65 in North Bend now.

[snow_wizard]

I'm kind of happy the ECMWF suite of models is showing a possible foggy inversion setting up for week two.  We have had basically no fog this autumn so far.

[snow_wizard]

5 minutes ago, DJ Droppin said:

Yeah the latest HRRR and even NAM 3km paint the same picture.

I think it will be windy, but destructive is overstating it.

[snow_wizard]

2 minutes ago, TT-SEA said:

Up to 65 in North Bend now.

I'm actually happy to see an honest to goodness torch for a couple of days.  Many of the great La Nina winters had that.

[Phil]

3 hours ago, snow_wizard said:

What we are going through right now is 1990 to a T.  It has been a frequent CPC analog as further evidence.

The crazy years we are referencing (2008/09, 1990/91, 1949/50, 1995/96, even ugly ones like 1999/00) are all +QBO. And they are extreme cases. IMO we’re looking in the wrong places because there are some (waning) peculiarities in the mean state that are triggering mirages.

IMO, if we want to make seasonal scale predictions, I think we need to derive them from the mean state, which is maturing canonical Niña/-QBO (descending), with a relatively narrow HC/retracted IPWP, -PMM/-PDO.

Then for a secondary pool of analogs relative to the initial, note the relative warmth in the subtropical stratosphere in 2021 vs climo for this stage it descending E shear, MJO/ERW superposition(s) and tendencies on that scale between the seasonal and the subseasonal through which the evolution of state(s) arise(s). 

[Gradient Keeper]

2 minutes ago, snow_wizard said:

I think it will be windy, but destructive is overstating it.

I think damaging winds are very possible for that area susceptible to westerlies blasting through the Strait.

[Phil]

1 hour ago, TT-SEA said:

Full 12Z EPS run... the east is going to turn cold.    That probably lines us up well for a pattern reversal in December.     Matt... December?

 

Recall Dr. Roundy’s filtered tropical forcing analogs have been dialed in on the cold November in the East for months.

Those same analogs suggest a transition to -PNA/GOA ridge and western trough in December. Which is where my thinking was/is, as well.

[Gradient Keeper]

2 minutes ago, Phil said:

Recall Dr. Roundy’s filtered tropical forcing analogs have been dialed in on the cold November in the East for months.

Those same analogs suggest a transition to -PNA/GOA ridge and western trough in December. Which is where my thinking was/is, as well.

Looks like a block setting us offshore and energy south of the Aleutians being held back. A conceivable progression if you ask me.

[snow_wizard]

They keep bumping up the forecast for the Skagit.  They have it right at record crest now.  Looks like the Nooksack is getting close to major also.  They only have the Stillaguamish at moderate.  That seems odd.

[snow_wizard]

13 minutes ago, Phil said:

The crazy years we are referencing (2008/09, 1990/91, 1949/50, 1995/96, even ugly ones like 1999/00) are all +QBO. And they are extreme cases. IMO we’re looking in the wrong places because there are some (waning) peculiarities in the mean state that are triggering mirages.

IMO, if we want to make seasonal scale predictions, I think we need to derive them from the mean state, which is maturing canonical Niña/-QBO (descending), with a relatively narrow HC/retracted IPWP, -PMM/-PDO.

Then for a secondary pool of analogs relative to the initial, note the relative warmth in the subtropical stratosphere in 2021 vs climo for this stage it descending E shear, MJO/ERW superposition(s) and tendencies on that scale between the seasonal and the subseasonal through which the evolution of state(s) arise(s). 

I've just been stating what the observed weather is doing and what CPC analogs show.  Hard to ignore.  I think you will be surprised by what happens.

I've mentioned 1970 repeatedly which was -ENSO , -QBO but you haven't commented on it.

[Phil]

33 minutes ago, DJ Droppin said:

Especially during a soon to be strong La Nina. If we were in an El Nino I would agree, or really it wouldn't matter as I expect all El Ninos to be warm a bit drier than average with endless split flow hell around ~140 W. NOPE!

18z GFS in 46 minutes

Those “expected” La Niña/El Niño patterns only reflect the mean/seasonal state. There is plenty of shorter term variability under all ENSO phases/amplitudes.

Rarely (if ever) does the same pattern continue all winter. That would be highly unusual.

The averaged DJF pattern *is* likely to reflect La Niña. But there will be variability from week to week.

[SilverFallsAndrew]

57 minutes ago, DJ Droppin said:

2008

 

No, this month is torching a lot more than 2008 did so far. Going to be wetter too. 

[snow_wizard]

13 minutes ago, DJ Droppin said:

I think damaging winds are very possible for that area susceptible to westerlies blasting through the Strait.

Yeah...I looked at the east entrance to the Strait again and it looks possible.

[Deweydog]

38 minutes ago, Mr Marine Layer said:

Then why would the cooling system come on?

If 70 was too hot we’d set it lower.

 

[Gradient Keeper]

5 minutes ago, snow_wizard said:

They keep bumping up the forecast for the Skagit.  They have it right at record crest now.  Looks like the Nooksack is getting close to major also.  They only have the Stillaguamish at moderate.  That seems odd.

[Phil]

6 minutes ago, DJ Droppin said:

Looks like a block setting us offshore and energy south of the Aleutians being held back. A conceivable progression if you ask me.

Eventually the ridging near the West coast should retrograde towards the GOA/Aleutians, perhaps somewhere between December 5-10?

The western ridging coming up is a temporary product of intraseasonal variability and dynamics related to the seasonal transition (which is still in progress).

I am not worried it. At all. The only thing we need to watch out for is excessive +EPO (some +EPO is fine).

I’m not worried about NAO/etc either. Not a huge factor in this type of evolution (unless it is massively positive).

[Phil]

In summary: there are no “tea leaves” to read regarding the ongoing pattern. It is temporary, transient, and will (probably) be replaced by a substantial -PNA type pattern sometime next month (arising from retrogression). Bookmark this post.

[Anti Marine Layer]

Just now, Phil said:

In summary: there are no “tea leaves” to read regarding the ongoing pattern. It is temporary, transient, and will (probably) be replaced by a substantial -PNA type pattern sometime next month (arising from retrogression). Bookmark this post.

start a new thread for it

[Deweydog]

1 minute ago, Phil said:

In summary: there are no “tea leaves” to read regarding the ongoing pattern. It is temporary, transient, and will (probably) be replaced by a substantial -PNA type pattern sometime next month (arising from retrogression). Bookmark this post.

Weren’t you predicting a warm December?

[TT-SEA]

7 minutes ago, Phil said:

In summary: there are no “tea leaves” to read regarding the ongoing pattern. It is temporary, transient, and will (probably) be replaced by a substantial -PNA type pattern sometime next month (arising from retrogression). Bookmark this post.

Dude... this is so wrong.   

[Anti Marine Layer]

14 minutes ago, Deweydog said:

If 70 was too hot we’d set it lower.

 

Usually the AC does not trigger until it's one degree warmer than the set temperature, so that would mean 71 is too hot.

GOETTL It will keep you cool but it's hard to spell.

[Phil]

15 minutes ago, Deweydog said:

Weren’t you predicting a warm December?

Warm start with transition to cool/stormy.

But caveat: I’ve already made a mistake this month (the pacific jet farther south than I expected). But the pattern is evolving as I thought (split flow coming second half of November).

On 10/14/2021 at 4:09 PM, Phil said:

Update: Okay, below is my “official” prediction.

Made some timing changes. Good chance I’m wrong, but what the hell, you miss 100% of the shots you don’t take.

FYI: Based on upper level conditions. Doesn’t factor in inversions, convergence zones, etc. I’m not good at predicting that stuff.

Nov: Warm/dry overall [ ehh ]. Drier south, wetter north (vs climo). Period of split flow mid/late month? Probably a blocky month but don’t think it’ll favor the PNW.

Dec: Slight warm lean. Dry to start, turns wet mid/late month? Timing might be off but suspect there’ll be a dry—>wet/stormy transition in there somewhere. Arctic air may build in western Canada later in the month, but (probably) remains bottled up. If it does make it south, I suspect there’ll be a tight N/S gradient. 

Jan: Slight cool lean, wetter than average. Suspect there’ll be a zonal period in there somewhere, perhaps analogous to 1998/99 or 2011/12, with an old school “January thaw” across most of the CONUS while PNW region is cool and stormy. Upstream/NPAC blocking is questionable..absent a compromised vortex I’d favor -WPO/-PNA/+EPO. Under a high(er) amplification scenario, an Arctic outbreak is possible.

Feb: Cooler than average, especially early in the month. Uncertain about precipitation, but would be surprised if it strayed too far from normal in either direction. Analogs are quite variable this month, which suggests any disruption to the PV/stratosphere and/or a significant MJO transit could prove decisive.

Mar: Lol. I don’t know. Let’s go with cold and anomalously wet and revisit it later.

These types of details are extremely difficult for me to predict months in advance, so minor to moderate errors will happen, even with the pattern somewhat resembling my expectations.

[Brian_in_Leavenworth]

Not the usual yearly flooding for NW Washington.

O.NEW.KSEW.FL.W.0080.211115T0327Z-211117T2351Z/
/NKSW1.2.ER.211115T0327Z.211116T1800Z.211117T1900Z.NO/
128 PM PST Sun Nov 14 2021

...FLOOD WARNING IN EFFECT FROM THIS EVENING THROUGH WEDNESDAY
AFTERNOON...

* WHAT...Moderate flooding is forecast.

* WHERE...Nooksack River At Ferndale.

* WHEN...From this evening to Wednesday afternoon.

* IMPACTS...At 20.5 feet, the Nooksack River will overflow levees
  and banks along the east bank of the river from Hovander Park
  downstream to Marietta, causing widespread flooding from near
  Ferndale downstream to the mouth...with swift waters in
  residential areas and over farm lands and roads. Erosion may
  damage some river banks.


* ADDITIONAL DETAILS...
  - At 1:15 PM PST Sunday the stage was 14.9 feet.
  - Forecast...The river is expected to rise above flood stage
    this evening to a crest of 21.2 feet late Tuesday morning. It
    will then fall below flood stage late Wednesday morning.
  - Flood stage is 18.0 feet.
  - Flood History...This crest compares to a previous crest of
    21.1 feet on 01/05/1984.
  - http://www.weather.gov/safety/flood

FLOOD WARNING IN EFFECT FROM THIS EVENING THROUGH WEDNESDAY
EVENING...

* WHAT...Major flooding is forecast. This approaches the flood of
  record.

* WHERE...Skagit River Near Mt. Vernon.

* WHEN...From this evening to Wednesday evening.

* IMPACTS...At 36.0 feet, the Skagit River will cause severe near
  record flooding from Sedro Woolley downstream through Mount Vernon
  to the mouth. Deep and swift flood waters will inundate and
  possibly damage many roads...farmlands and residential areas.
  Levees may be damaged.  Flood areas will also include headwaters...
  tributaries...and other streams in the Skagit basin. This level
  for this location corresponds to a Phase 1 flood in the Skagit
  County flood system.

* ADDITIONAL DETAILS...
  - At 12:15 PM PST Sunday the stage was 26.7 feet.
  - Forecast...The river is expected to rise above flood stage
    late this evening to a crest of 37.1 feet Tuesday afternoon.
    It will then fall below flood stage Wednesday morning.
  - Flood stage is 28.0 feet.
  - Flood History...This crest compares to a previous crest of
    37.0 feet on 11/11/1906.
  - http://www.weather.gov/safety/flood

[TacomaWaWx]

64 here…warmest day in 3 weeks. Haven’t had anything measurable in a couple hours now. 

[TacomaWaWx]

1 hour ago, snow_wizard said:

I think it will be windy, but destructive is overstating it.

The amount of rain we’ve had recently could make a run of the mill storm be more impactful. We will see what happens but it could be pretty windy tomorrow. 

[TT-SEA]

Some nostalgia for Phil... raining at his old stomping grounds.