12Z thursday update; LOOK there Stands the VIRGINIAN like a stone Wall

Now that the midday models have run we can take a look at the pattern change in some more detail and we continue to see the operational run of the midday DFS screwing things up after day 7 ina BIG way.

I want to be clear on this particular point. This is not simply a matter of not accepting the operational runs of the GFS because it's warm and I'm biased towards the cold or because it offers a solution that I like versus a solution that I don't like. There is serious scientific reasoning behind runs over the last several days are bogus and of little value. Of course that doesn't mean I am guaranteed to be correct.... and it certainly is possible that the operational runs of the GFS code against all probability turn out to be valid. But even if I turn out to be wrong I would still have to go in this direction in any similar situation because 9 times out of 10 a model outlier that goes against this much model consensus is always wrong.

To begin with one has to consider which of the models have over the last several weeks been for more consistent with the warm pattern and which model has been overdoing the cold along the northern portions of the US near the Canadian border. Clearly the European model has been far more correct in the operational GFS.

Second because the GFS has a truncation problem after 180 hours the operational solution in particular often ends up with goofy solutons from 192 to 384 HOURS. By model truncation I am referring to the problem that the GFS model has in its resolution which is significantly different after 180 hours. From 0 to 180 hrs the operational GFS grid points are 55 KM apart... but after 180 hrs the grid point spacing is essentially DOUBLED. Of all the global weather models which deal in the Medium & Long range forecasts ONLY the GFS model has THIS particular problem. There is a long history as to why the folks at EMC / NCEP decided to set up the GFS this way ... without going to too much detail EMC believes that running the model four times today at two different resolutions is more useful than running the model twice a day at the same resolution. Of course the folks at EMC are completely long on as but that's not to stop them from continuing to do it nor are they going to do it that their entire premise is bullshit.

Third... all of the models have a particular bias or problem or tendency and good forecasters have to keep these model biases or tendencies in mind. In this particular case the cold bias of the GFS... which is a tendency of the model to overdo the power of the northern branch of the jet stream also known as the polar jet is a well-documented problem with the operational GFS... and. To a lesser degree the GFS ensembles. It is not suddenly a problem which has appeared out of nowhere because you may not have known about it.

Again if you take a look at the operational GFS at the D10... you can see this huge Ridge over Southeast states BUT again when you compared the 12z Thursday op GFS to the other members of the 12z GFS ensembles you see major differences.

Taking look at this link of the 12z Thursday and ensembles -- the operational run of the GFS which is on the top row in the far left hand corner... notice the huge Ridge or closed contour over Georgia and Florida of 588 dm. Now go through the rest of these models and see you can find any other member but also shows a huge 588 close contour over the Southeast.

If you can find one which shows that... you're probably drunk or mentally retarded . The issue is not whether there will be a Ridge over the Southeast coastJan 14---- their most certainly will be. The issue is whether there is a huge close condor dome sitting over the Southeast US which is what the operational run of the GFS is showing.

http://www.meteo.psu.edu/~gadomski/ENSHGT_12z/f240.html

One we compare the insomnia versus the operational run
http://www.meteo.psu.edu/~gadomski/ENSHGTAVGNH_6z/f240.html

We again see that most of the RED lines on the map on the RIGHT are significantly further suppressed over the Southeast than what the Operational run is showing.

And we can see the same thing for late on January 15... the map on the left shows ensemble mean with the trough now covering MOST most of the US... while the map of the right shows the white lines ( operational 12z THURSDAY GFS heights) with a very strong enhanced Ridge over the Southeast. But again if you can see for most of the RED lines and most of the GREEN lines and most of the BLUE lines they are all further south and east and what the operational run -- WHITE lines-- are showing.

Finally let me talk about the midday European which in my opinion is very promising. The operational Thursday 12z European closes off 500 low over the Southwest which the OP Ecmwf has been doing for several runs. This is what I was talking about earlier today.... But more importantly at D9-10 the 500 low retrogrades into the eastern Pacific off the California coast and this does two VERY important things.

First having a block in the eastern Pacific MEANS that the Northern branch / Polar Jet is much stronger and comes much the with further south then the 12z op GFS or 12z GFS ensembles.. and delivers significant amounts of cold air into the central and eastern US

Second the REX block ..... becomes a storm of pump for eight feature which the look constantly ejected energy or shortwaves from the larger 500 low off the Southern California coast. These shortwaves would move east fairly quickly and interact with the frontal boundary over the lower Plains and Deep South.

This is what set the stage for several significant over running events and with always cold air in place-- at least according to the date 10 operational European... the first significant winter weather threats for much of the eastern US somewhere between January 15-20.