December 2014 Observations for the Pacific Northwest

[Gradient Keeper]

I wouldn't call the long range GEM garbage.  Pattern progression looks okay at days 8-10.  Lacks amplification though.

 

http://img.meteocentre.com/models/gemglb_amer_00/GZ_D5_PN_240_0000.gif

True, if it were centered 500 miles north.

[Deweydog]

If we are marching toward something spectacular, we're clearly in the false start mode with regard to models.  Taking any of what's being spit out right now at face value is dumb.  

[Snow]

If we are marching toward something spectacular, we're clearly in the false start mode with regard to models. Taking any of what's being spit out right now at face value is dumb.

You have a point but we can start looking at trends. Models are pointing towards the potential for Arctic air to arrive. We can also start to speculate if certain runs are outliers or not. For instance tonight's 00z GFS run won't verify in the long range. This is because if you take a look at the D+8 analogs it has a correlation rate of 0.754 but then the D+11 is at 0.890. This should raise a red flag and the ensembles showed it by having the op as a warm outlier.

[snow_wizard]

If we are marching toward something spectacular, we're clearly in the false start mode with regard to models.  Taking any of what's being spit out right now at face value is dumb.  

 

I totally agree.  Sometimes I go into pretty deep comment on a model run.  Whenever I do that it's simply wrapping up what the model shows, not how likely it is to happen.

[snow_wizard]

You have a point but we can start looking at trends. Models are pointing towards the potential for Arctic air to arrive. We can also start to speculate if certain runs are outliers or not. For instance tonight's 00z GFS run won't verify in the long range. This is because if you take a look at the D+8 analogs it has a correlation rate of 0.754 but then the D+11 is at 0.890. This should raise a red flag and the ensembles showed it by having the op as a warm outlier.

 

With the last cold snap the analogs being shown in the composite were the first clue something good was going to happen.  First time I've seen that happen.  Tonight there were a few standouts.  Your point about the low correlation score on the 8 day composite is excellent.

[MossMan]

How did the 0z Euro look? 6z GFS? Or is everyone waiting on the 12z's?

Currently 28 degrees and frosty!

[TT-SEA]

Looks like a spectacular sunrise is in the works. Perfectly placed band of mid-level debris.

[MossMan]

Looks like a spectacular sunrise is in the works. Perfectly placed band of mid-level debris.

Yeah I noticed that as well!! The radio said its 50 degrees in Seattle, not sure if that is correct but it's 26 here in Arlington!

[stuffradio]

It is or was 28 here.

[TT-SEA]

[SilverFallsAndrew]

12z once again dumps everything just east.

[Tyler Mode]

The sunrise wasn't as nice as I was expecting, but any sunrise is a good sunrise!

 

Pics:  http://weathercrazy.smugmug.com/Landscapes/Winter-20142015

 

That link includes photos from other sunrises too.

 

http://weathercrazy.smugmug.com/Landscapes/Winter-20142015/i-p5Ppc72/0/L/59.%20G%20Mt.%20Hood%20Sunrise%20Pan-L.jpg

[gsax]

12z once again dumps everything just east.

12z GFS for Everett, WA doesn't look that bad.  http://wxweb.meteostar.com/sample/sample.shtml?text=KPAE

I would post a picture, but it doesn't let me.

[stuffradio]

524 thickness and -7 850 isn't terrible for Abbotsford next Wednesday. There is a lot of time for things to be even colder (or warmer).

[HighlandExperience]

12z GFS for Everett, WA doesn't look that bad.  http://wxweb.meteostar.com/sample/sample.shtml?text=KPAE

I would post a picture, but it doesn't let me.

 

Ya it doesn't look that bad if you want some mountain snow in the WA/BC. 850 temps are not torching.

 

Much better than what we just experienced this past week.

[Alex_Snakes]

Ya it doesn't look that bad if you want some mountain snow in the WA/BC. 850 temps are not torching.

 

Much better than what we just experienced this past week.

 

As long as it isn't torchy on Christmas, I'm happy.

[liquidsnow]

As long as it isn't torchy on Christmas, I'm happy.

The 12z ECMWF isn't your friend then. Take a look at that massive ridge guys....

 

A snowstorm for the Eastern US on Christmas Eve.

[ShawniganLake]

The 12z ECMWF isn't your friend then. Take a look at that massive ridge guys....

 

A snowstorm for the Eastern US on Christmas Eve.

The ridge axis is offshore.  Looks chilly on Christmas morning to me.  That isn't a torch.

 

http://mp1.met.psu.edu/~fxg1/ECMWF0.5_12z/f240.gif

[Black Hole]

Late-December might be too early, but the transition in early/mid January has been expected by TheNewBigMack and myself for a long time now.

I'm on board too.

[TT-SEA]

The 12z ECMWF isn't your friend then. Take a look at that massive ridge guys....

 

A snowstorm for the Eastern US on Christmas Eve.

 

Does not look too bad...

 

http://old.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!240!North%20America!pop!od!oper!public_plots!2014121512!!chart.gif

[Deweydog]

The 12z ECMWF isn't your friend then. Take a look at that massive ridge guys....

 

A snowstorm for the Eastern US on Christmas Eve.

 

I still can't get over that name... What a gas!!!  

[liquidsnow]

Whoops, I was looking at hour 192.

[luvssnow_spokane]

Just to reiterate and confirm that the 12z does not look like a torch by any means! Not epic arctic but on the colder side with 850mb temps hovering around -6 to -7 Christmas day. I'm not a big fan of the placement of things at this point (could push cold east) but this is still so far out I do not even want to speculate - I will leave that to others hopes, wishcasts and analysis. I will say this, the trends are still fairly positive and I am hopeful for a cooler Christmas than some from our pasts.  Plenty of room to get better too! 

 

 

[SilverFallsAndrew]

Wow, this place kind of died. Must be a Monday.

[Jesse]

Wow, this place kind of died. Must be a Monday.

Everyone realized that it's not going to snow on Winter's Hill anytime soon. And really, what's the point then?

[IbrChris]

12z Euro ensembles...little additional insight here versus 24h ago. Still a substantial risk for a fairly benign event with most of the cold air sliding to our east. Plenty of support for a full-on arctic blast though as well...we will need to watch a couple things in addition to ridging near 160 W: Degree and orientation of Greenland block and presence of a SE US ridge. The latter seems to be more necessary for any sustained event in the PNW. About half of ensemble members are signaling a very strong block over W Alaska/Bering Sea as we enter the 11-15 which is highly correlated to PNW arctic blasts in the historical record.

[Parksvillewx]

12z Euro ensembles...little additional insight here versus 24h ago. Still a substantial risk for a fairly benign event with most of the cold air sliding to our east. Plenty of support for a full-on arctic blast though as well...we will need to watch a couple things in addition to ridging near 160 W: Degree and orientation of Greenland block and presence of a SE US ridge. The latter seems to be more necessary for any sustained event in the PNW. About half of ensemble members are signaling a very strong block over W Alaska/Bering Sea as we enter the 11-15 which is highly correlated to PNW arctic blasts in the historical record.

 

Great analysis! Thanks

[IbrChris]

Great analysis! Thanks

Thought it needed livened up a bit in here.

[Parksvillewx]

Thought it needed livened up a bit in here.

 

Agreed. Not much chatter here lately. Maybe that will change with the upcoming period looking more interesting.

[MossMan]

Thought it needed livened up a bit in here.

Yeah the forum was lit up with excitement yesterday afternoon, then it just completely died when the 0z GFS came out last evening. Thanks for your analysis, that is awesome info!! 

[bainbridgekid]

FWIW the Parallel GFS is definitely a lot better than the Operational at hour 240. Ridge is pretty amplified and in a nice location. Pretty close to an arctic blast pattern. Operational not so much.

 

Operational:

 

http://www.tropicaltidbits.com/analysis/models/gfs/2014121518/gfs_z500_mslp_namer_37.png

 

Parallel:

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014121518/gfsp_z500_mslp_namer_41.png

[Snow]

12z Euro ensembles...little additional insight here versus 24h ago. Still a substantial risk for a fairly benign event with most of the cold air sliding to our east. Plenty of support for a full-on arctic blast though as well...we will need to watch a couple things in addition to ridging near 160 W: Degree and orientation of Greenland block and presence of a SE US ridge. The latter seems to be more necessary for any sustained event in the PNW. About half of ensemble members are signaling a very strong block over W Alaska/Bering Sea as we enter the 11-15 which is highly correlated to PNW arctic blasts in the historical record.

 

http://oi62.tinypic.com/j7bvcg.jpg

Great analysis, I'm confident the upcoming 00z EURO tonight will continue off what it showed last night.

[Snow]

FWIW the Parallel GFS is definitely a lot better than the Operational at hour 240. Ridge is pretty amplified and in a nice location. Pretty close to an arctic blast pattern. Operational not so much.

 

Operational:

 

http://www.tropicaltidbits.com/analysis/models/gfs/2014121518/gfs_z500_mslp_namer_37.png

 

Parallel:

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014121518/gfsp_z500_mslp_namer_41.png

Yeah the GFS is really struggling in the long range. I'm glad we get to see the upgraded version now and it's more like the EURO.

[Snow]

I just looked at the analog composites and it's laughable at this point. The 12z GFS D+8 had a correlation of 0.731 and the 18z GFS D+8 had 0.715. The GFS is way too aggressive shoving all that Arctic air east. Don't be surprised if the upcoming 00z GFS tonight keeps showing what the 12z/18z showed. It might take a while for it to come around.

[Phil]

The initial shot will likely slide east, perhaps glancing the PNW..but I suspect a slight retrograde of the EPO ridge in early January will offer a better chance, IMO.

 

Obviously, the core of the cold will not be centered over the PNW. That never happens..

[Skagit Weather]

As of today, Hurricane Ridge, Mount Baker, Stampede Pass, Mission Ridge, Crystal Mountain, White Pass, and Mount Hood Meadows are all at record low snow levels. This is unprecedented with some of the periods of record extending back to 1926 (Mount Baker). Only Paradise has more than a foot on the ground and most of the mountains are 0-10% of normal. On the GFS it appears that this weekend will be another warm torch so the ski areas might have zero snow at the beginning of Christmas week.

 

http://data.nwac.us/CLISNO/CLISNO.TXT

[Gradient Keeper]

Because why not?….
[Model Countdown]
00z GFS 2 hours 10 minutes
00z GEM 2 hours 24 minutes
00z ECMWF 4 hours 36 minutes

[HighlandExperience]

As of today, Hurricane Ridge, Mount Baker, Stampede Pass, Mission Ridge, Crystal Mountain, White Pass, and Mount Hood Meadows are all at record low snow levels. This is unprecedented with some of the periods of record extending back to 1926 (Mount Baker). Only Paradise has more than a foot on the ground and most of the mountains are 0-10% of normal. On the GFS it appears that this weekend will be another warm torch so the ski areas might have zero snow at the beginning of Christmas week.

 

http://data.nwac.us/CLISNO/CLISNO.TXT

 

I went up to Alpental yesterday to survey the lack of snow. The roadway itself has about a foot of snow in the valley leading up to Alpental, with barely an inch at the base (if even that).

 

The lack of coverage is pathetic right now. Looks like we might have a shot at significant snow on Saturday followed by some warm rain <_>

 

I thought last year was pathetic, but this year is worse!!!  I am starting to have flash backs from 04/05 ski season.

 

Hope the 00z runs give us a path toward redemption.

[snow_wizard]

The 18z parallel GFS shows Arctic air just about to enter WA at day 10.

 

This is sure a weird situation.  We may go into a big cold wave with almost no snow on the ground in the mountains.  A normal warm ENSO winter would actually do better in the mountains the first half of the winter.  Expect big surprises to come.

[wx_statman]

The initial shot will likely slide east, perhaps glancing the PNW..but I suspect a slight retrograde of the EPO ridge in early January will offer a better chance, IMO.

 

Obviously, the core of the cold will not be centered over the PNW. That never happens..

 

It happened in December 1968. Needless to say, that's not normal.