griteater

12z GFS v16 is also a touch south at 500mb from last run out to hr90

12z GFS

Out to hr87, the GFS is a little south this run with the wave track

On 06z GFS v16, the track is North Bama to NW SC to Kill Devil Hills

Few thoughts: 12z NAM: agree, better wave track this run - farther south 06z GFS / GFS v16: both were in the west to east slider storm camp. Main diff I see is that the GFS just isn't as dynamic aloft compared to the GFS v16 on the 06z run. You can see that here with the 850mb wind field. So again, the winter precip with this one is going to be dynamically generated on the NW side of the 850 low as NWS mentioned, so you want this to be as strong as possible aloft

Storm 2 only on the Euro

Yep classic gulf low, but it warms inland...I posted the loop in the mid range thread...action picking up

Euro follows up the weekend storm with a classic NW Gulf to NE Gulf Miller A winter storm, though it goes negative tilt with the wave and warms inland

It looks similar to GFS v16 at 500mb, just not as strong. Spoke revolving around the 50/50 low drops due south into NY/VT, and that collapses the amplitude of the height field off the Mid-Atlantic coast, so the wave just slides east off NC. Who knows which model is correct, but the west to east slider like GFS v16 and Euro are what many in NC east of the Mtns and Foothills would want, and the more amped CMC/UKMet is what the Mtns/N Foothills/into VA would want.

There's a whole lot going on with respect to the strength and track of the wave based on how it interacts with the upstream kicker wave coming into Colorado behind it and the configuration and strength of the downstream 50/50 low with various spokes rotating around it (pretty typical though with model wars and how they are handling pieces at 500mb). For 00z, the UKMet is well south with the track of the wave thru GA like the GFS v16, but the wave is strong and it has more amplitude, which can be seen by the 558 height line reaching up just to the south of Long Island. Wave on the GFS's doesn't have as much amplitude there

CMC slingshots the wave into E TN so it gets snow farther north into VA, but also into W NC UKMet tracks the wave like the GFS brothers...from N MS to Cape Hatteras

Looks like 00z GFS v16 has snow piling up in parts of W NC

Trends today have been for a little stronger storm tracking a little farther south. I don’t think it’s going to trend back to a very weak system but track is up in the air, IMO

Here's the trend loop on the Euro with the last image being from the 18z run (that run only goes out to hr90). It has a small bump south on the 18z run.

GEFS trend loop over the past 24 hours for Thursday at 7PM. Stronger North Atlantic ridge. Stronger 50/50 low. Taller ridge behind the storm wave. All aids in producing the trend of a farther south wave track.

AnthonyM is honking here as we move forward...."we're starting to see the NWP move away from the IO to Maritimes look now and more of a W PAC to IO look instead, as Matt alluded to earlier. evidence is increasing for a high impact period ahead." What he is saying is that the MJO models have been forecasting the upcoming tropical forcing in more of the 2-3-4-5 phases....but he is seeing (and maybe the models are correcting) to more of a W Pac to East Pac to Atlantic to Indian Ocean type circuit (Phase 7-8-1-2)...favorable for troughing in the eastern U.S. You can see that here with this product below. We never want to see enhanced convection / tropical forcing in the E Indian Ocean and Indonesia / Maritime Continent in winter for cold. Green areas are divergent flow aloft = enhanced convection.

Euro Ensemble Mean pattern for Jan 11-18

An improving temperature profile shown here on the Euro Ensemble Mean for Jan 9-18 as colder air filters south from Northern Canada into the Great Lakes (GEFS and GEPS ensembles are in agreement)

Euro is currently the farthest south with the wave track (Canadian bumped south this run and is similar)

The 18z GFS v16 has an abrupt ridge going up out west from day 10 on

Don't think it matters much in this setup though as I don't think the setup is going to allow for low level cold air to move in with a well positioned sfc high to the north, but we will see

Here is the Euro Control run at 500mb and at the Surface. Wave enters the west coast in Oregon and is forced to slow down and dive down into the SE as the flow backs up over the Canadian Maritimes and North Atlantic with the developing blocking. Simply put, you want this wave to be as strong as possible, and tracking a bit south of you as the temperatures needed for snow would come on the N and NW side of that track as heights crash. Stronger wave = stronger temperature crash. Surface temps would be the last to fall, so things like time of day could be a factor in a marginal temp setup. You could make the case that the small wave tracking thru the Great Lakes toward the end of the loop is disrupting flow so that the surface high above the Great Lakes isn't allowed to build in to help the low level temperatures out ahead of the storm (2nd loop)....but on the prior run, that small wave wasn't there and it didn't make a difference.

Agree. Just comparing tonight's runs between the new GFS v16 (1st image) and the current GFS (2nd image), look at how the current GFS just drops the North Atlantic blocking by hr204 while the new GFS v16 maintains it...think the current GFS is bunk there

Going into mid-Jan, there's a 'big battle' going on between the developing blocking in the North Atlantic bullying the pattern and shifting the entire height pattern south (you especially saw that in days 8-10 on the 12z Euro)...going up against a Pacific pattern that contains a strong zonal jet with low anomalies in the Gulf of Alaska

Been thinking about this in recent days...regardless if the Euro shows warm and snowless or winter storms, I suspect it will be the better model in this pattern. It's already been better with the stratospheric evolution and should be better with the stratosphere - troposphere coupling. Also, it historically does better with larger global features like high latitude blocking. Note from Simon Lee on Twitter: "GEFS & CFSv2 have 64 vertical levels, while ECMWF's ensemble has 91 and more of those are in the stratosphere (38 above 100 hPa vs. 24 in CFS). So, I anticipate ECMWF is on the right lines, as models with greater vertical resolution perform better"