December 2016 Observations and Model Discussion for the Pacific Northwest

[SilverFallsAndrew]

Today's CFS is wet for January with near average temps. February looks below average with a lot of lowland snow opportunities. 

[SilverFallsAndrew]

December 11th and Timberline is up to a 96" base. Pretty astounding. 

[Perturbed Member]

Always.  

 

Has the euro really outperformed the wrf by such a big margin?

[Phil]

The reason the recent NPAC block was able to amplify poleward so prolifically was because the PV was exceptionally weak..it met no thermal or kinetic resistance. However, in doing what it did, it allowed the TWG/U-wind components and PV column to re-strengthen, given the lack of supplementary driving, as was aforementioned.

 

So, now we're back to square one going forward. First, we need either a massive Eurasian wavebreaking regime or +WPO regime to promote efficient poleward WAFz, which will hopefully knock up the PV/NAM. From there, the next round of NPAC wavebreaking can be more efficient with supplementary help.

[Timmy Supercell]

It's looking increasingly likely that by the end of December I'll have more than the monthly normal snowfall in Klamath Falls. Maybe 15-18" or more. But probably not a Dec 2015 repeat.

 

I think you live a bit farther south than me.

Although you change your name every two weeks so it's hard to keep track. Are you windy/blizzard/tundra/prince/arctic blast?

 

So that's where blizzard and tundra went!!

[Perturbed Member]

18z GFS is still a go for Thursday. Low is a bit stronger and a hair further north. 

[bainbridgekid]

Tomorrow night is probably Seattle area's best chance.

Agreed. That's what I've been saying for several days.

 

The models try to bring the cold air in too soon almost every single time. It's frustrating. Guess it's their way of making up for pushing the cold air out too quickly as well.

[SilverFallsAndrew]

The low is a little further north yet on the 00z...By Thursday it'll be making landfall at Juneau.

[MossMan]

Agreed. That's what I've been saying for several days.

 

The models try to bring the cold air in too soon almost every single time. It's frustrating. Guess it's their way of making up for pushing the cold air out too quickly as well.

Just too bad though since the cold air is so D**n close. I've had moderate rain here all morning....if it were just a little colder...

[Timmy Supercell]

The low is a little further north yet on the 00z...By Thursday it'll be making landfall at Juneau.

 

Think southern OR gets a decent amount of snow or is it not looking very big here yet?

[bainbridgekid]

The low is a little further north yet on the 00z. 18z..By Thursday it'll be making landfall at Juneau.

It's very similar to the 12z though. Basically right at the CA/OR border.

[SilverFallsAndrew]

WRF was interesting for Thursdays storm...Kept everything just a little south and east. 

[SilverFallsAndrew]

Think southern OR gets a decent amount of snow or is it not looking very big here yet?

 

Hard to say. As modeled you would probably go snow to rain and then back to snow as the low pulls off to the east. 

[Heavy Snow]

18z GFS is still a go for Thursday. Low is a bit stronger and a hair further north.

Yeah, there's going to be potential for lots of wrap-around moisture in the form of Snow as the L heads East. Reason for the big snow totals models are throwing out.

[Jesse]

Think southern OR gets a decent amount of snow or is it not looking very big here yet?

Hopefully you will be able to dodge the bullet.

[BLI snowman]

WRF was interesting for Thursdays storm...Kept everything just a little south and east.

Gorge outflow shouldn't be raging at least, as modeled. Light easterly flow is so much better.

[SilverFallsAndrew]

As modeled PDX area people would probably want the low to set up about 50 miles further north. The heaviest swath of snow is about Eugene to Wilsonville.

[Jesse]

18z GFS is still a go for Thursday. Low is a bit stronger and a hair further north.

Putting us in position for the inevitable northward jog in the final 12-24 hours leading up to the event to give us 45 degree rain and a low tracking north of Forks.

[Timmy Supercell]

Hopefully you will be able to dodge the bullet.

 

I don't mind it snowing. Just not my favorite type of weather. lol

And when I get months like last Dec it looks impressive on facts and figures. What I will hope for is walking-friendly conditions, no ice.

[Perturbed Member]

The low is a little further north yet on the 00z...By Thursday it'll be making landfall at Juneau.

 

Have we actually seen a situation where all the models start by showing a low making landfall in northern cal but 84 hours later send it into central WA coast or Vancouver island or something ridiculous? I can't imagine it is that common when all the models are reasonably close in their solutions. 

[Jesse]

As modeled PDX area people would probably want the low to set up about 50 miles further north. The heaviest swath of snow is about Eugene to Wilsonville.

It will track north. Things always track north. We need to be seeing these adjustments in the day leading up to the event. Not now.

[Perturbed Member]

As modeled PDX area people would probably want the low to set up about 50 miles further north. The heaviest swath of snow is about Eugene to Wilsonville.

 

Lets leave those 50 miles alone for now, the models can move the low up 50 miles in the final 24 hours. We need that buffer

[MR.SNOWMIZER]

Winter weather advisory for Bellingham

[Jesse]

PDX warming up nicely today on SW winds. A taste of Thursday's weather?

[HighlandExperience]

[SilverFallsAndrew]

PDX warming up nicely today on SW winds. A taste of Thursday's weather?

 

Have you ever heard of "despair casting?" It is the opposite of "wishcasting."

[snow_wizard]

The ECMWF is on board with a decent snow chance on Thursday. Nice to see. Yet another run showing 850s bottoming out at -10 this week for Seattle. I can't understand why people are still worried about the cold. The moisture is likely to be our problem for snow. Not a single run of any model has shown it not getting cold.

[BLI snowman]

Have we actually seen a situation where all the models start by showing a low making landfall in northern cal but 84 hours later send it into central WA coast or Vancouver island or something ridiculous? I can't imagine it is that common when all the models are reasonably close in their solutions.

Only when cold air is directly involved.

[snow_wizard]

It's going to keep trending north. Good chance it will come in right at the mouth of the Columbia.

I sure hope so. I'm going to be blunt and say I don't care if NW OR gets screwed. I am sick of getting no snow.

[Timmy]

PDX warming up nicely today on SW winds. A taste of Thursday's weather?

Snowing 20 miles from it.

[Perturbed Member]

The ECMWF is on board with a decent snow chance on Thursday. Nice to see. Yet another run showing 850s bottoming out at -10 this week for Seattle. I can't understand why people are still worried about the cold. The moisture is likely to be our problem for snow. Not a single run of any model has shown it not getting cold.

 

Agree, looks to be a matter of how that low on Thursday tracks.

[Deweydog]

Interesting setup with multiple models wanting to develop a coastal surface low as the southern steam low ejects. I can't think of previous examples of that.

[snow_wizard]

As for the Seattle area over the next couple of days...our best shot is precip /convergence holding on into Monday night. Decent shot that will happen to some degree.

[SilverFallsAndrew]

I sure hope so. I'm going to be blunt and say I don't care if NW OR gets screwed. I am sick of getting no snow.

 

You got more snow than my location at 1600' did on Thursday. So you have that...

[MossMan]

The ECMWF is on board with a decent snow chance on Thursday. Nice to see. Yet another run showing 850s bottoming out at -10 this week for Seattle. I can't understand why people are still worried about the cold. The moisture is likely to be our problem for snow. Not a single run of any model has shown it not getting cold.

NWS Seattle said in the morning discussion that it won't be as cold as first thought this week so I was assuming the -850's were fizzling.

[snow_wizard]

Interesting setup with multiple models wanting to develop a coastal surface low as the southern steam low ejects. I can't think of previous examples of that.

Somebody could get nailed big time with that.

[Timmy Supercell]

You got more snow than my location at 1600' did on Thursday. So you have that...

 

Often in region wide events I'll get less than folks in the lowlands will.

In Feb 2014, Salem got freaking 5-6x more snow than I did.

[BLI snowman]

I sure hope so. I'm going to be blunt and say I don't care if NW OR gets screwed. I am sick of getting no snow.

 

Every weenie for themselves! Getting deadly serious out there!!

[snow_wizard]

NWS Seattle said in the morning discussion that it won't be as cold as first thought this week so I was assuming the -850's were fizzling.

The cold should be sufficient.

[Deweydog]

Somebody could get nailed big time with that.

BIG TIME!!!