December 2014 Observations for the Pacific Northwest

[snow_wizard]

Honestly that is always the place of disagreement year after year. I do not see this being all that puzzling.

You missed the point of the post.

 

The ECMWF is not amplified. That is the point of disagreement on that model compared to the others.

[snow_wizard]

So tonight's tally is this.

 

GEM - A thing of beauty

GFS - very blocky and moderately cold (block too close to be Arctic)

Parallel GFS - Excellent block placement, close to being great

ECMWF - No amplification so it flops

[luvssnow_spokane]

You missed the point of the post.

 

The ECMWF is not amplified. That is the point of disagreement on that model compared to the others.

.

 

My apologies ...

[epiceast]

You missed the point of the post.

 

The ECMWF is not amplified. That is the point of disagreement on that model compared to the others.

My guess would be splitflow. Whenever it shows a cut off low during a pattern that looks like an offshore ridge will build, we end up getting splitflow. This might be a really weird Euro run, but that would be a first.

[snow_wizard]

The really weird thing is the ECMWF is the model showing the dead on perfect MJO wave for a NW Arctic blast around New Years. Maybe it saw some mitigating factor on this run. Obviously we still have no idea what New Years will look like.

[Snow]

So tonight's tally is this.

 

GEM - A thing of beauty

GFS - very blocky and moderately cold (block too close to be Arctic)

Parallel GFS - Excellent block placement, close to being great

ECMWF - No amplification so it flops

The 00z EURO Ensembles will be very important tonight. My opinion is that the operational will be a huge warm outlier again.

[snow_wizard]

My guess would be splitflow. Whenever it shows a cut off low during a pattern that looks like an offshore ridge will build, we end up getting splitflow. This might be a really weird Euro run, but that would be a first.

It actually jumped the gun on a very cold pattern possibility earlier in the week also. It has had its problems lately.

[Gradient Keeper]

So tonight's tally is this.

 

GEM - A thing of beauty

GFS - very blocky and moderately cold (block too close to be Arctic)

Parallel GFS - Excellent block placement, close to being great

ECMWF - No amplification so it flops

Yep, and it shows that after day 5 we still have major model disagreement on how to handle things. That means in my opinion we're no closer with 00z runs tonight on knowing how this plays out. Too much volatility with this large scale pattern change.

 

Onto 12z....

[snow_wizard]

The 00z EURO Ensembles will be very important tonight. My opinion is that the operational will be a huge warm outlier again.

Do you have access to the graphics for the individual ensemble members?

[Snow]

Do you have access to the graphics for the individual ensemble members?

No just the mean but the difference for YVR between the operational and ensemble mean has been around -8C. It's gotten close though, last run was -4C/-5C. There are still a lot of cold members. The -8C line is still very close to YVR.

 

http://download.ecmwf.org/data/web248/get_legacy_plot-web248-20141220202346-15407-1312.gif

[Parksvillewx]

What time does the Euro ensemble come out?

[ShawniganLake]

What time does the Euro ensemble come out?

1230ish I believe. I wouldn't bother waiting up for it. Not going to be impressive.

[Snow]

What time does the Euro ensemble come out?

Sometime between midnight and 1am I think.

[Parksvillewx]

1230ish I believe. I wouldn't bother waiting up for it. Not going to be impressive.

 

I'm trying to keep that small piece of hope alive. Everything is always 8 days away though..

[ShawniganLake]

Gfs ensemble is showing 2 cool troughs. One on Xmas. One a couple days after. Neither looks arctic. No cold members around New Years. A few cold members showing up a couple days after 2015 begins.

[ShawniganLake]

Then there is this. Did someone predict coast to coast cold in early January? .…note the proper use of punctuation. I am not driving, however.

 

[PacNW44]

Significant retrogression on 0z Euro ensemble.....early Jan.

[ShawniganLake]

Significant retrogression on 0z Euro ensemble.....early Jan.

Weatherbell? Graphics?

[Phil]

Weatherbell? Graphics?

He's correct..though there's definitely disagreement in there. Shows a -PNA/-EPO/SE ridge.

[Gradient Keeper]

BIG improvements on ECMWF Ensembles. There are also now several cold members on the GEM too. GFS, meh, not so much.

[Snow]

06z GFS-Parallel alert for any nightowls still up. It looks really good. Here are the 500mb Geopotential Height maps for hour 204 and 240. The upper level high is strong and in a good spot. A slight shift West would even be better.

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122106/gfsp_z500a_namer_35.png

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122106/gfsp_z500a_namer_41.png

[Gradient Keeper]

06z GFS-Parallel alert for any nightgowns still up. This looks really good. Here are the 500mb Geopotential Height maps for hour 204 and 240. The upper level high is strong and in a good spot. A slight shift West would even be better.

 

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122106/gfsp_z500a_namer_35.png

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122106/gfsp_z500a_namer_41.png

It's not bad at all. 560dam heights over southern Alaska is key here.... yep, just a bit further west and it's very GEM like, very cold/snowy potentially. Onto 12z....

 

[Model Countdown]

Next up....

12z GFS in 4 hours 25 minutes

12z GEM in 5 hours 20 minutes

12z ECMWF in 6 hours 53 minutes

[Snow]

It's not bad at all. 560dam heights over southern Alaska is key here.... yep, just a bit further west and it's very GEM like, very cold/snowy potentially. Onto 12z....

 

[Model Countdown]

Next up....

12z GFS in 4 hours 25 minutes

12z GEM in 5 hours 20 minutes

12z ECMWF in 6 hours 53 minutes

Yeah very promising run. The parallel run looks so much different from the regular run. The GFS upgraded because it was falling behind the EURO, well if it turns out to be correct it would mean that the upgrade is having good early success. Right now it's the GEM/GFS-Parallel vs the EURO/GFS-Regular. Either the GFS-Parallel upgrade was a huge success or it's having major beta problems. I'm hoping the upgrade is a success.

[westcoastexpat]

Models are really struggling with the upcoming pattern. Even small perturbations in the jet will have a large impact on the set-up during the Christmas-New Years stretch. It's an exciting (and scary) time to be model watching, especially since this is the time of year most want lowland snow.

 

Not looking too promising for my neck of the woods. Colder temperatures look probable but I could care less. I would rather 32 degrees and snow than a day of below 20 F and windy conditions. Hopefully something dynamic shapes up on the mesoscale with the intruding cold and low level jet energy but I won't be counting my chickens. 

 

My holidays officially start on the 23rd and run until the 1st so I would absolutely love a bullseye of snow near the border at that time 

 

If I've learned anything in my short time as a (Canadian) met, it's that the GEM is very good at picking up a general pattern in the long range, but can be poor in the placement/amounts of a system. I've also learned not to bother even looking at the GFS outside of the short range.

[jaya]

06z GFS-Parallel alert for any nightowls still up. It looks really good. Here are the 500mb Geopotential Height maps for hour 204 and 240. The upper level high is strong and in a good spot. A slight shift West would even be better.

 

Too close for snow but good for good cold and a lot of wind in the northern interior of western Washington.

[jaya]

No just the mean but the difference for YVR between the operational and ensemble mean has been around -8C. It's gotten close though, last run was -4C/-5C. There are still a lot of cold members. The -8C line is still very close to YVR.

 

Euro is pay, but GFS and Canadian can be found at http://mp1.met.psu.edu/~fxg1/ewallmref.html

[jaya]

It actually jumped the gun on a very cold pattern possibility earlier in the week also. It has had its problems lately.

I believe all of the models jumped the gun on the November event as well. I think that is a common theme - as I have seen that in years past as well.

[jaya]

It actually jumped the gun on a very cold pattern possibility earlier in the week also. It has had its problems lately.

The ECMWF has had a few more issues of late. I'm not sure what changes have been made, but this year's performance isn't where it had been. Of course some of that could be due to the weather pattern itself.

[Gradient Keeper]

Good morning,

 

12z GFS is underway .... Here we go....

[MR.SNOWMIZER]

The 6z was a fat turd.

[Gradient Keeper]

HR 48 Op

 

http://www.tropicaltidbits.com/analysis/models/gfs/2014122112/gfs_z500_mslp_namer_9.png

 

Parallel

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122112/gfsp_z500_mslp_namer_9.png

[MossMan]

Currently on page 457 of the Jan 2012 event...my eyes now hurt from reading but man it's like I'm reliving each moment, what a great time that week was!

 

Hopefully we have some good 12's today!

[jaya]

The 6z was a fat turd.

Look at the parallel. It will hopefully perform better with its higher resolution. You can find it at: http://www.tropicaltidbits.com/analysis/models/?model=gfsp&region=us&pkg=mslp_pcpn_frzn&runtime=2014122112&fh=6&xpos=0&ypos=116.  Change the Region to NHEM or NOAM.

[Gradient Keeper]

HR 72 Op

http://www.tropicaltidbits.com/analysis/models/gfs/2014122112/gfs_z500_mslp_namer_13.png

 

Parallel .. - Huge differences already

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122112/gfsp_z500_mslp_namer_13.png

[MR.SNOWMIZER]

Thanks man.

 

Look at the parallel. It will hopefully perform better with its higher resolution. You can find it at: http://www.tropicaltidbits.com/analysis/models/?model=gfsp&region=us&pkg=mslp_pcpn_frzn&runtime=2014122112&fh=6&xpos=0&ypos=116. Change the Region to NHEM or NOAM.

[Gradient Keeper]

So just look only at the parallel ?

 

HR 96

http://www.tropicaltidbits.com/analysis/models/gfsp/2014122112/gfsp_z500_mslp_namer_17.png

[jaya]

So just look only at the parallel ?

 

HR 96

It seems to develop lows much better than the operational (that is over the short time I've been looking at it).  Notice the differences between the op and para with development over Texas, N/NE of HI and over the Bering Sea.  This will have huge impact on the forecast just a few days out.

[jaya]

It seems to develop lows much better than the operational (that is over the short time I've been looking at it).  Notice the differences between the op and para with development over Texas, N/NE of HI and over the Bering Sea.  This will have huge impact on the forecast just a few days out.

 

The development was before the image I quoted. Sorry if there is any confusion.

[Gradient Keeper]

It seems to develop lows much better than the operational (that is over the short time I've been looking at it).  Notice the differences between the op and para with development over Texas, N/NE of HI and over the Bering Sea.  This will have huge impact on the forecast just a few days out.

There are many differences that I notice.

[jaya]

Let's keep an eye on that low around HI and over the western Bering Sea.  It looks like things happen right after this period. http://www.tropicaltidbits.com/analysis/models/?model=gfsp&region=nhem&pkg=z500_mslp&runtime=2014122112&fh=78&xpos=0&ypos=319