December 2019 Weather Discussion for the PNW

[ShawniganLake]

Is your body ready for the doom the druncle is about to bestow upon us?

Looks like it’s going to dig the January 2nd-3rd trough even more offshore.

[ShawniganLake]

At least Friday is looking dry now. Maybe a good day to take the lights down.

[SilverFallsAndrew]

Looks like it’s going to dig the January 2nd-3rd trough even more offshore.

 

Yep. Our best mountain snow may be on New Year's. Then a brief torch which is a fitting way to begin the new year. 

[snow_wizard]

The 12z EPS has the lowest PNA forecast yet dropping a bit below -3 in combination with a slightly -EPO.  Numbers like that are going to deliver.

 

 

[TigerWoodsLibido]

The 12z EPS has the lowest PNA forecast yet dropping a bit below -3 in combination with a slightly -EPO.  Numbers like that are going to deliver.

 

The models sadly don't look to be showing much action.

[snow_wizard]

The 18z GFS continues to push up a ridge over us days 5 and 6 instead of simply crushing the ridge while it's just off the coast.  It's obvious this is where the GFS and Euro end up going such different ways. 

[snow_wizard]

The models sadly don't look to be showing much action.

 

Trust me.  Numbers like that will deliver if they actually happen.  Teleconnection forecasts have proven useful with these events before.

[SilverFallsAndrew]

The trough next weekend is a bit colder on the 18z, just delayed from previous runs, but it gets here with sub 522 thickness dropping south of Eugene by Sunday morning. 

[OysterPrintout]

If the pattern plays out like the GFS has been depicting for next weekend then the 18z is definitely a step in the right direction.

[Timmy Supercell]

This will be better than '20-'21, in fact there are '22-'23 vibes.

[snow_wizard]

If the pattern plays out like the GFS has been depicting for next weekend then the 18z is definitely a step in the right direction.

 

It actually does get decently cold next weekend with sub 522 thickness over SEA.

[TT-SEA]

It actually does get decently cold next weekend with sub 522 thickness over SEA.

 

 

Also shows a strong SW wind all weekend.    Not going to be too interesting in the lowlands... but great for the mountains.

[SilverFallsAndrew]

Also shows a strong SW wind all weekend.    Not going to be too interesting in the lowlands... but great for the mountains.

 

The colder weather at the surface will probably be early next week when the surface high pressure builds in right after that cold trough. 

[Deweydog]

The trough is faster than a jackrabbit on a date! Goes coast to coast in less than two days.

[High Desert Mat?]

Also shows a strong SW wind all weekend. Not going to be too interesting in the lowlands... but great for the mountains.

Jesus. Contradiction is your friend. Let someone feel good for more than five minutes. You’re getting really old.

[Kayla]

The cold that Alaska has been having over these last couple of weeks reminds me a lot of the end of January 1989. We all know what happened about 10 days after that.

 

Very promising to have all that cold air on this side of the globe. I really like our chances for next month.

[snow_wizard]

This GFS run is looking better for sure.

[TT-SEA]

Jesus. Contradiction is your friend. Let someone feel good for more than five minutes. You’re getting really old.

 

Jesus. I will post what I want. Screaming SW winds are not our friend... pretty important detail.

 

There are literally thousands of posts on here that I could validly contradict and don't.

[Deweydog]

The cold that Alaska has been having over these last couple of weeks reminds me a lot of the end of January 1989. We all know what happened about 10 days after that.

 

Very promising to have all that cold air on this side of the globe. I really like our chances for next month.

1989 was a pretty big outlier, in case people are thinking that’s a predictable progression. Probably a significant result of the preceding SSW. Lots of things pegged the meter for that baby and typically our remarkably cold air masses occur when things are in flux up there and we tap into some cross-polar flow.

[snow_wizard]

The cold that Alaska has been having over these last couple of weeks reminds me a lot of the end of January 1989. We all know what happened about 10 days after that.

 

Very promising to have all that cold air on this side of the globe. I really like our chances for next month.

 

Jan 1989 has been an analog for a while on the CPC site.  I think our best January of the century so far is a pretty legit possibility.

[Kayla]

1989 was a pretty big outlier, in case people are thinking that’s a predictable progression. Probably a significant result of the preceding SSW. Lots of things pegged the meter for that baby and typically our remarkably cold air masses occur when things are in flux up there and we tap into some cross-polar flow.

 

I mean a SSW is definitely still on the table as well. Bizarre pattern progression but history proves it's possible.

[FroYoBro]

The GFS looks cool with mountain snow. Big improvement over those ridge solutions. 

[snow_wizard]

Much better GFS run.  Big ridge in the East by day 10 or just after.  GOA block looking healthy.

[snow_wizard]

The GFS looks cool with mountain snow. Big improvement over those ridge solutions. 

 

My sights are much higher than mountain snow, but that will be one of the early benefits of the coming change.

[TT-SEA]

I mean a SSW is definitely still on the table as well. Bizarre pattern progression but history proves it's possible.

Was wondering what is happening with the SSW. Last year it took a couple weeks or more for the effects to take hold if I remember correctly.

[Brian_in_Leavenworth]

February 1989 had some pretty cold temps, very strong winds especially Whatcom County, and lasted only about 5 days.  Dec 2008 and February 2019 were much better IMO.  Snow did come in March, but a separate event.

[Deweydog]

I mean a SSW is definitely still on the table as well. Bizarre pattern progression but history proves it's possible.

Just about anything is possible, just pointing out it would be an unusual progression. Better bet is that cold moving out, shaking the etch a sketch and keeping things unconstipated up there.

[Kayla]

Was wondering what is happening with the SSW. Last year it took a couple weeks or more for the effects to take hold if I remember correctly.

 

GFS and Euro show a Siberian SSW event in about 7-8 days.

[TigerWoodsLibido]

GFS and Euro show a Siberian SSW event in about 7 days.

 

Haven't they been showing SSW signals that keep on going away?

[SilverFallsAndrew]

I think best January of the Century will be a tall order. 

[Gradient Keeper]

As others have mentioned the Day 6-7 trough is colder. Sub 522 thickness PDX, 850s -8c. PDX-EUG light gradient -2 to -3mb. Snow level 750-500' at times. Overnight into morning hours slushy snow nearly everywhere is likely. It would be nice if that played out. After day 8-10 500mb pattern clearly better than 12z. It's close to greatness and even losing the initial Kona low still doesn't change the overall evolution with the Gulf of Alaska/Eastern Aleutian block. Good things ahead! YEAH! C'MON!!!!

 

00z GFS in 4 hours 37 minutes

 

Think Cold and SNOW!!!! C'MON!!!!

❄ ❄ ☃ ❄ ❄

[Gradient Keeper]

GFS and Euro show a Siberian SSW event in about 7-8 days.

Oh really? That would be a game changer.

[TigerWoodsLibido]

Ensembles rolling out.

[seattleweatherguy]

GFS and Euro show a Siberian SSW event in about 7-8 days.

Face value how cold would it get? Historic?

[Deweydog]

GFS and Euro show a Siberian SSW event in about 7-8 days.

Looks pretty meager. Hardly puts a dent in the PV.

[Kayla]

Oh really? That would be a game changer.

 

Yeah...not massive but hopefully enough to shake things up.

[seattleweatherguy]

Was our coldest temps due to an SSW event?

[TigerWoodsLibido]

Looks like the operational is now going to be a cold outlier.  ​ 

[TT-SEA]

Face value how cold would it get? Historic?

There is no "face value" with a SSW. It has to happen and then we see how it shakes out.

[Kayla]

Looks pretty meager.

 

Might just be all we need though.