PNW December 2022, winter might be coming; but mostly canceled.

[Cascadia_Wx]

5 minutes ago, SilverFallsAndrew said:

I wonder what the spaghetti chart looks like. I like that better than smoothed means, gives us a better glimpse into the range of possibilities the ensembles are showing.  

To the rescue Andrew.  

 

I’d say it looks decent, if not improved.

[Deweydog]

1 minute ago, MossMan said:

Even though we have lost the TIM model, birds have massively increased their bird seed consumption in my bird feeder over the last few days…It’s coming in January. And Matt is one good lookin’ fella.

Fixed.

[Mid Valley Duck]

6 minutes ago, SilverFallsAndrew said:

I wonder what the spaghetti chart looks like. I like that better than smoothed means, gives us a better glimpse into the range of possibilities the ensembles are showing.  

A small camp of cold members. Interestingly the control run is in the arctic camp

[Snownerd3000]

9 minutes ago, WeatherGeek2022 said:

nah you're right. lows in the 20s and *maybe* highs in the mid thirties is probably best case scenario as sad as that is.

This is the climo response but as presented this isn't a climo setup and it isn't every year we have as much cold air on tap as is advertised. Models will continue to waffle a bit and that spread in the EPS will tighten(hopefully for accuracy sake and for everyones psyche) as we get to the weekend.

[Blizzard777]

45 minutes ago, Rubus Leucodermis said:

My money is on the Euro being closer to the truth. Because it typically is.

I’m going to agree for 10 points 

My trust is also in the King 

[Snownerd3000]

Is there such thing as an ensemble median?  Some of these extremes really swing the average.

[TT-SEA]

4 minutes ago, MossMan said:

Even though we have lost the TIM model, birds have massively increased their bird seed consumption in my bird feeder over the last few days…It’s coming. 

I am on team Euro!   But Matt said the best part of the Euro is pure nonsense.  

[Winterdog]

I really hate to see the east coast get cold and snowy for Christmas while we get warm rain.  This is going the way 90% of our hoped for cold outbreaks go.  39 after a so far high of 40, overcast all day.

[Phishy Wx]

Euro has been consistent, GFS has been, well the GFS.  that's got to count for something i'd think?

[WeatherGeek2022]

7 minutes ago, Winterdog said:

I really hate to see the east coast get cold and snowy for Christmas while we get warm rain.  This is going the way 90% of our hoped for cold outbreaks go.  39 after a so far high of 40, overcast all day.

such a horrible fate for us

[TT-SEA]

14 minutes ago, Phishy Wx said:

Euro has been consistent, GFS has been, well the GFS.  that's got to count for something i'd think?

EPS and GEFS have been quite consistent as well.   Surreal situation.   Can't remember anything like this.

[Cold Snap]

14 years ago today was the start of something truly special!

[Kolk1604]

6 minutes ago, Cold Snap said:

14 years ago today was the start of something truly special!

And 14 Years and 4 days later will be the start of something historic... Maybe? 

[Rubus Leucodermis]

50°F rain south of Everett for Christmas. Snow for Mossman and me! Book it!

[SouthHillFrosty]

Just now, Rubus Leucodermis said:

50°F rain south of Everett for Christmas. Snow for Mossman and me! Book it!

Nope ice storm!

[Cloud]

As suck as it is... this to me actually looks more realistic. Shunting it east is more common. 

We'll see. 

[Rubus Leucodermis]

1 minute ago, SouthHillFrosty said:

Nope ice storm!

Will trend south. It is a time-honoured tradition that Portland gets mostly ice during winter weather events.

Sorry, I don’t make the rules, I just report them.

[ShawniganLake]

Wow. This de escalated quickly. 

[WeatherGeek2022]

1 minute ago, Cloud said:

As suck as it is... this to me actually looks more realistic. Shunting it east is more common. 

We'll see. 

I really envy the east coast after seeing this looks like winter cancel for us

[Rubus Leucodermis]

16 minutes ago, WeatherGeek2022 said:

such a horrible fate for us

Yes, there has never been a mild, rainy Christmas in PNW history. Children will end up scarred for life.

[Snownerd3000]

1 minute ago, ShawniganLake said:

Wow. This de escalated quickly. 

We all know by 8 tonight the 0z will show something mostly different and we'll either like it or hate it but it won't matter bc we won't put any weight behind it until we see what happens with the 0z Euro.

[Deweydog]

One way to look at… the sooner the pattern blows up, the sooner it can reset.

[fubario]

latest sea NWS discussion 2:15pm...presented w/o commentary.

.LONG TERM /SATURDAY THROUGH TUESDAY/...General theme for the
longer term will be colder temperatures as well as potential for
lowland wintry precipitation. However, there is significant
amount of uncertainty into timing and extent of troughing, and
thus cold air for the Pacific Northwest that is briefly reviewed
in this section.

The aforementioned ridge offshore late week will begin to flatten
as an upper trough slides south across British Columbia towards
the Pacific Northwest. Over the last 12 hours or so, the general
trend in guidance (both ensemble/deterministic) has been to slow
the progress southward of this trough, and thus have more moderate
temperatures on Saturday. Precipitation chances increase later
Saturday and through Sunday with the troughing influence.
Uncertainty grows in the placement of the trough by Sunday, in
particular the troughs extent southward. The focus will be on
ensembles rather than deterministic guidance for this period, as
prior deterministic runs have fluctuated a bit more, as well as
being general outliers compared to the entire ensemble guidance.
The WPC Cluster Analysis for the 24 hour period ending 00z Mon
shows the uncertainty in the ensembles. In general, the GFS
ensembles lean towards more of a ridging influence, compared to
the ECWMF which has the bulk of the troughing further south across
the interior Northwest. This has rather significant impacts on
the temperatures with 27% of the Cluster Analysis being above the
ensemble mean temp, and approx. 36% below ensemble mean, with some
variation in between. This also plays a role in how much
precipitation is expected on Sunday with the frontal system moving
southward, with higher QPF having a correlation with further
troughing. At this time, the best opportunity late Saturday -
Sunday for lowland snow potential would be northern areas,
specifically north of SEA, with stronger southwesterly winds to
the south. Although the potential exists further south as well
depending on the amount of moisture still in play later Sunday-
Sunday night.

Forecasts become even more uncertain for Monday-Tuesday with
guidance really not in agreement of the placement of troughing
early next week. As noted in the previous paragraph, GFS ensembles
continue to suggest more ridging for the Pacific Northwest
compared to ECMWF and CMC. Given the period being almost a week
out, have opted with the NBM. Although from a probabilistic
standpoint, there is a 20 degree spread in high temperatures on
the NBM for Seattle using the 10-90 th percentile for Tuesday,
showing the wide range in uncertainty for this period. At least
some of the guidance is also focusing on a potential overrunning
event during the Monday-Tuesday period as well, bringing
additional chances for lowland snow. After reviewing this AFD, the
main advice is to continue to monitor the weather forecast over
the next week for this period, with colder temperatures expected
and potential for lowland snow. JD

&&

 

[Terreboner]

I'm going to laugh when all guidance puts us back in the deep freezer with the 00z runs.

[runninthruda206]

Someone tell me how to feel 

[Hawksfan2008]

3 minutes ago, fubario said:

latest sea NWS discussion 2:15pm...presented w/o commentary.

.LONG TERM /SATURDAY THROUGH TUESDAY/...General theme for the
longer term will be colder temperatures as well as potential for
lowland wintry precipitation. However, there is significant
amount of uncertainty into timing and extent of troughing, and
thus cold air for the Pacific Northwest that is briefly reviewed
in this section.

The aforementioned ridge offshore late week will begin to flatten
as an upper trough slides south across British Columbia towards
the Pacific Northwest. Over the last 12 hours or so, the general
trend in guidance (both ensemble/deterministic) has been to slow
the progress southward of this trough, and thus have more moderate
temperatures on Saturday. Precipitation chances increase later
Saturday and through Sunday with the troughing influence.
Uncertainty grows in the placement of the trough by Sunday, in
particular the troughs extent southward. The focus will be on
ensembles rather than deterministic guidance for this period, as
prior deterministic runs have fluctuated a bit more, as well as
being general outliers compared to the entire ensemble guidance.
The WPC Cluster Analysis for the 24 hour period ending 00z Mon
shows the uncertainty in the ensembles. In general, the GFS
ensembles lean towards more of a ridging influence, compared to
the ECWMF which has the bulk of the troughing further south across
the interior Northwest. This has rather significant impacts on
the temperatures with 27% of the Cluster Analysis being above the
ensemble mean temp, and approx. 36% below ensemble mean, with some
variation in between. This also plays a role in how much
precipitation is expected on Sunday with the frontal system moving
southward, with higher QPF having a correlation with further
troughing. At this time, the best opportunity late Saturday -
Sunday for lowland snow potential would be northern areas,
specifically north of SEA, with stronger southwesterly winds to
the south. Although the potential exists further south as well
depending on the amount of moisture still in play later Sunday-
Sunday night.

Forecasts become even more uncertain for Monday-Tuesday with
guidance really not in agreement of the placement of troughing
early next week. As noted in the previous paragraph, GFS ensembles
continue to suggest more ridging for the Pacific Northwest
compared to ECMWF and CMC. Given the period being almost a week
out, have opted with the NBM. Although from a probabilistic
standpoint, there is a 20 degree spread in high temperatures on
the NBM for Seattle using the 10-90 th percentile for Tuesday,
showing the wide range in uncertainty for this period. At least
some of the guidance is also focusing on a potential overrunning
event during the Monday-Tuesday period as well, bringing
additional chances for lowland snow. After reviewing this AFD, the
main advice is to continue to monitor the weather forecast over
the next week for this period, with colder temperatures expected
and potential for lowland snow. JD

&&

 

Basically none of us have any idea what’s going to happen one thing I’ll say is we constantly write off the GFS in favor of the EURO when the roles are flipped. Until the EURO shifts there is no reason not to be cautiously optimistic. 

[GHweatherChris]

[Cascadia_Wx]

7 minutes ago, Deweydog said:

One way to look at… the sooner the pattern blows up, the sooner it can reset.

Re-set 12/27 to 1/7 por favor!

[Deweydog]

3 minutes ago, runninthruda206 said:

Someone tell me how to feel 

Good

[Rubus Leucodermis]

2 minutes ago, Terreboner said:

I'm going to laugh when all guidance puts us back in the deep freezer with the 00z runs.

I’m going to laugh regardless.

If this is a snow fail, it will be a snow fail. Getting massively dejected won’t change the outcome.

[Terreboner]

Just now, Rubus Leucodermis said:

I’m going to laugh regardless.

If this is a snow fail, it will be a snow fail. Getting massively dejected won’t change the outcome.

Me too.

[Cascadia_Wx]

Meanwhile, back in the unsatisfying hell that is current reality, PDX may be on track to scoring their first sub-40 high of the season today.

37/29 day here with fog and low clouds sticking around most of the day. Chilly.

[Rubus Leucodermis]

Who said a regionwide event was not possible? Rain for all!

 

[Terreboner]

Just now, Rubus Leucodermis said:

Who said a regionwide event was not possible? Rain for all!

 

So when it shows frigid arctic air it is a joke, but when it shows warm onshore flow it is a certainty?

[WeatherGeek2022]

1 minute ago, Rubus Leucodermis said:

Who said a regionwide event was not possible? Rain for all!

 

rain for christmas oh hell naw

[Kolk1604]

Here we go. The 18z EMCWF has initialized and goes out to Friday afternoon 

[Cascadia_Wx]

2 minutes ago, Terreboner said:

So when it shows frigid arctic air it is a joke, but when it shows warm onshore flow it is a certainty?

Seems like he’s being about 10x more annoyingly pretentious than usual today. Analog???

[Rubus Leucodermis]

2 minutes ago, Terreboner said:

So when it shows frigid arctic air it is a joke, but when it shows warm onshore flow it is a certainty?

Basically yes. And there is a very good reason for this: climo.

Mild and rainy is the norm west of the Cascades. Therefore, a clown range model calling for it is much more likely to verify than one calling for cold and snow.

Thank you for playing.

[Deweydog]

3 minutes ago, Cascadia_Wx said:

Re-set 12/27 to 1/7 por favor!

Can only give you through the 31st. I need all 31 days of Jan Brady. Got a lot riding on this as I think Fred is gonna eat my weenie like Kobayashi if it busts.

[SilverFallsAndrew]

If the EURO caves tonight we will need to crown the GFS the new KING. We should be getting a preview of early returns in about 3 1/2 hours with the GLOBAL ICON.