December 2014 Observations for the Pacific Northwest

[Phil]

He's been spot on so far... why continue to question him? Even if he isn't spot on for his Jan 1-10th call, he still has done amazingly well.

Thanks, appreciated. Hopefully my luck continues.

[Front Ranger]

Looking at the parallel....

 

 

 

Looks like it will end up better than operational past day 7 again.

[IbrChris]

Not all -NAOs are the same, though..I don't really agree. In cases like 2010-11, I agree they're detrimental in that they'll enhance momentum transfer in the wrong area(s). However, in cases like 1968-69, upstream breaking was quite diluted, relatively, and it was the -NAO response that did the trick.

Also the modeled Baffin block wouldn't have extended nearly as far south this time as it did in 1968. I would say a setup similar to 1968 is the exception rather than the rule for PNW arctic blasts and it would take a simple compilation of mean 500 mb pattern during PNW arctic blasts of the past ~75 years to establish the more favorable pattern. I would agree that the 1968 block location/orientation was more favorable than a textbook Greenland block. That almost always results in a western ridge absent an EPO block over Alaska. That is the key, having the EPO ridge as Front Ranger mentioned, not the NAO state except that a SE ridge doesn't happen during -NAO.

 

Anyhow thanks for the discussion. 1968 is an interesting case for sure.

[SilverFallsAndrew]

Looks like it will end up better than operational past day 7 again.

 

Uh huh...

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122500/gfsp_z500a_namer_32.png

[MR.SNOWMIZER]

Thanks, appreciated. Hopefully my luck continues.

It's not luck. You've done your homework.

[IbrChris]

I would say a NAO state has obviously most influence in the eastern third of the US as it serves similarly to the EPO ridge to lock down the long wave pattern. +NAO is almost without fail bad for prolonged cold over the eastern US but will allow for a seasonable look with brief cold intrusions modulated by frontal systems with southerly return flow in between. A -NAO can also help the central US by favoring Great Lakes cyclogenesis which in turn aids the flow of arctic air out of central Canada. In my opinion it has the least effect out west and I don't see it as a causal mechanism like the EPO block.

[bainbridgekid]

Well this would be fun.

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122500/gfsp_z500_mslp_namer_37.png

[SilverFallsAndrew]

The operational basically undercuts the block it looks like. If not it would be blast city.

[SilverFallsAndrew]

Wow....

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122500/gfsp_z500_mslp_namer_39.png

[IbrChris]

It's not luck. You've done your homework.

I like the idea of a cold to very cold west the first 6-10 days of Jan although until relatively recently I was skeptical of the placement and timing. We all know the tendency is for a Plains dump. Whether Phil called it or not I'll leave to others to decide. The sample size is too small and the methodology unclear to me so I can't form an opinion either way. If kudos seems deserved then kudos to those who feel they deserve it.

[bainbridgekid]

The operational basically undercuts the block it looks like. If not it would be blast city.

Big overrunning potential there if it does get undercut. The operational is close to a very snowy setup with all the cold air just North of the border.

 

Parallel does not get undercut and blasts us with arctic air at day 9 with a low sliding down the Coast.

 

Lots of potential either way.

[richard mann]

Possibly .... .

 

I would think, for a few different reasons—foremost, where considering a potentially more obscured exchange of ideas more climatological taking place within a more general type discussion thread, .. the idea of working to make that exchange perhaps a bit more clear—with your reply where looking at something perhaps less appreciable more generally, your making sure not, to adopt a more emphatic tone.

 

Congruity, is really all I have in mind here. ....

[Poulsbo Snowman]

I like the idea of a cold to very cold west the first 6-10 days of Jan although until relatively recently I was skeptical of the placement and timing. We all know the tendency is for a Plains dump. Whether Phil called it or not I'll leave to others to decide. The sample size is too small and the methodology unclear to me so I can't form an opinion either way. If kudos seems deserved then kudos to those who feel they deserve it.

 

As best as I can tell, he's been spot on--with not only with what to expect, but also the timing.  Problem for me is his knowledge is a little too advanced for me.

[richard mann]

He's been spot on so far... why continue to question him? Even if he isn't spot on for his Jan 1-10th call, he still has done amazingly well. 

 

You've apparently, missed the point of my comment. 

[SilverFallsAndrew]

Unreal parallel run and not a bad operational run. The operational is closer to greatness in the long term than you think.

[MR.SNOWMIZER]

Full on blizzard ar hr 228.

[Phil]

I would say a NAO state has obviously most influence in the eastern third of the US as it serves similarly to the EPO ridge to lock down the long wave pattern. +NAO is almost without fail bad for prolonged cold over the eastern US but will allow for a seasonable look with brief cold intrusions modulated by frontal systems with southerly return flow in between. A -NAO can also help the central US by favoring Great Lakes cyclogenesis which in turn aids the flow of arctic air out of central Canada. In my opinion it has the least effect out west and I don't see it as a causal mechanism like the EPO block.

Our most significant blasts actually tend to occur in +NAO regimens..1994 and 2014 are good examples.

[richard mann]

Well this would be fun.

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122500/gfsp_z500_mslp_namer_37.png

 

"Cut off .. retrograde". (?) .. Interesting certainly. I think there's still potential to hope for better.

[SilverFallsAndrew]

Oh good lord

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122500/gfsp_z500a_namer_41.png

[Gradient Keeper]

Wow....

[MR.SNOWMIZER]

Oh good lord Photo shop!!

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122500/gfsp_z500a_namer_41.png

[SilverFallsAndrew]

The parallel GFS is like a Christmas gift. At least Jesus loves me...

[MR.SNOWMIZER]

This January could be the one. Wow.

[richard mann]

Wow....

 

.. plenty "cold". Although, ... 

 

— Hopefully, for the broader PNW, this more substantial cold books a bit more east to allow some amount of room for a main moisture element.* .. What's shown pattern-wise here is one "main" for lower lever .. CA, snow. 

 

*... I'm seeing some reasons to think that it (cold.) might just, myself.

[IbrChris]

The parallel GFS is like a Christmas gift. At least Jesus loves me...

Model Jesus delivered the goods this Christmas Eve. We're still waiting on GOLU Jesus.

[Gradient Keeper]

Coldest since 1968? This is amazing and now we have quite good agreement run-to-run consistency with the 12/18/00z parallel for a major regional arctic blast. Also, it seems apparent the models in the short term day 4-7 have trended colder and 00z is no exception digging the arctic trough more sharply and holding it over us for quite awhile. Sensational run. A real Christmas Gift to us all!

[MR.SNOWMIZER]

I expect future runs to be even colder. With the increased digging to the sw wouldn't be surprised to see more action as far as moisture popping up In the models.

[Gradient Keeper]

Finally, the Canadian is on board for the initial blast at day 4-7!

[Gradient Keeper]

00z GEM HR 114 850mb

http://www.tropicaltidbits.com/analysis/models/gem/2014122500/gem_T850_nwus_20.png

[Gradient Keeper]

Wow... GEM shows the blast comes quickly from the northeast

[Gradient Keeper]

00z GEM HR 126 HOLY BABY COWS

http://www.tropicaltidbits.com/analysis/models/gem/2014122500/gem_T850_nwus_22.png

[Phil]

Where's Jim? He should be foaming at the mouth right about now.

[ShawniganLake]

Finally, the Canadian is on board for the initial blast at day 4-7!

Hallelujah.

[MR.SNOWMIZER]

Stop dj I'm getting scared.

[MR.SNOWMIZER]

Where's Jim? He should be foaming at the mouth right about now.

probably tired of getting harassed.

[Gradient Keeper]

Models definitely trending much colder in the short term.....

[Phil]

Tim conveniently disappears when models show an exciting solution..wasn't he touting the GEM as a guru just this morning?

[Bryant]

probably tired of getting harassed.

The harasser is probably proud of himself. Seems to be his form of enjoyment on here.

[epiceast]

I must have been a bad boy this year, Santa has little time left to keep the temperatures above 0 for New Year's Eve.

[MikeInEverett]

Can't look at the models right now, I see it looks good in the long range, but does it look like Seattle has a good chance of snow on Sunday?