Carvers Gap

Pretty amazing how different the pattern looks with those big highs showing up in the Northern Plains.  Basically flattens the pattern out and prevents cutters on modeling...On the GFS, there are now three events to track inside of 10 days.  They are small but better than what we typically get at this time of year.

It appears the 12z GFS has rediscovered the potent slp next weekend...amazing how that happens over and over again.  Now, it is a warmer system as their is a low in the Lakes.  But plenty of time for that to change.  For a progressive model like the GFS to have that.   My guess would be(if real) a more wound-up system further inland.  

As Holston mentioned...going to have to keep an eye on that the system Tuesday into Wednesday.   Both the 12z ICON and the GFS are touting 1040+ highs.  Reminds me of the system a couple of weeks ago.  Probably cold chasing rain...but that is big cold chasing rain.  Also, will it develop a wave along the front per the icon?

...And the 0z Euro w a tease way out there.  Interesting to see the models really looking to bring a system nearly due north out of the GOM at that d8-10 range.  That threat has never really materialized inside of d6 or 7.  With the sharp EPO ridge out West, it does make sense.  Would not be surprised to see one of those materialize in the d5-6 range sort of out of the blue OR just a thread that was "rediscovered."  Again, it is not uncommon for global models to lose storms around d7 and then find them again.

Oddly, I am not as worried about timing(maybe I should be)...just want that big high.  The two ingredients in a set-up without Atlantic blocking are an active jet and a good source of cold.  The GFS and CMS have those...and both have energy in the pattern at about the right time given the range we are at which is a week+.   

And sure enough, the GFS finally finds its storm.  The key is whether that big high is real.  I think the southern stream is going to be active.  The CMC has a 1044 high on it...let's see where it goes.  Those big highs, for example, are similar to what caused the snow a few weeks ago.  The are potent.

Even though the "big one" wasn't on this GFS run, still plenty to be encouraged about...the big high was there, but trailing.  Still a very active pattern with three pieces of energy in the pattern.  If that big high shows up, someone is going to pay the pipe in an active pattern IMHO.  Pay me now or pay me later. 

All three operational (GEM, GFS, GEM) have it is some form or another.  The Euro is missing the cold high on this run...had it at 12z yesterday.  This is a storm that has been popping up on models suites for a few days if I remember correctly.  So, pretty good signal there.  Like we had a couple of weeks ago, the strength of that high is important with no blocking out front.  If we can get a 1040 hp over the top, lots of wintery precip is possible.  A 1050+ high would be crazy.  Still a long way to go...just like 30 more runs of the GFS.  LOL.  I will say that modeling does often pick up big events from decent range.  Is this one of those events?  I guess time will tell.  Looks like EPS/GEFS do have some support for this in terms of mslp placement.

1053 high parked over the top.  

12z Euro/EPS cooking up something late next week?

57 minutes ago, tnweathernut said:

Maybe, but the moisture stream off the Pacific still looks good.  Keep that look consistently and you'd think we have to score eventually. 

Just meaning I wasn't overly impressed with current SSTs or forecasted ones.  I think it is good enough to get us through winter...weaker the better in my book as long as we don't dip to a nada.  And yes, moisture train looks good for this month at least and prob normalish after that.

12z GEFS again looks cold from about 144 to the end of the run....variability prior to that.  The EPS ridge is just massive.  Have to think if that verifies, it is going to be much colder than modeled.  And there was really not sign of it letting up.  As always, have to be careful of a trough getting tucked under that ridge - how many times have I said that?  LOL.  Again, I think the Nino-ish forcing mechanism will kick it out.  As for the Nino, starting to look a bit putrid.  This may very well be a true weak El Nino, very weak.

Pretty interesting to see ridging events appear in the East only to be muted or erased as we draw closer.  Looks like we may very well have a significant cold shot right in the middle of what was supposed to be another ridging event.  Definitely a trend(ridge going West after being modeled East) to keep an eye on.  

I think right now, there is a storm signal(maybe multiple) after December 10th.  Often big storms will precede a cold outbreak.  A cutter wouldn't surprise me...but if that cuts, it will deliver bitterly cold air.   Then that boundary likely sets the stage for an overrunning event.  Best case scenario is a Miller A followed by cold and snow.  Worst case is a cutter that drives the boundary to Cuba.  I like what I am seeing so far...lots of options on the table.  Some are good and some are bad.  The Euro also tends to over-amp systems while the GFS is progressive.  At this range, just tough to know...but that is a cold, cold set of EPS/GEFS ensembles.  I suspect were are nowhere close to this working itself out.  Pretty impressive.  

8 minutes ago, TellicoWx said:

Exactly, if PNA can't hold to assist the EPO, then its wasted

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The problem with the Euro is that it messes around in the Southwest and is wrong about 2/3 of the time.  And that bias causes it to be slow sometimes.  The Euro has often been too warm this fall.  The GFS can sometimes be too quick with cold - right idea often but a few days too fast.  However, if one blends those two looks and the timing, that is a pretty good set-up for cold and snow in the East beginning about d10-12.  Probably also worth pointing out that often times modeling will underestimate how far south that cold gets.  I do think the ENSO set-up is going to force that trough out of the West.  I would not be surprised to see a big high settle into the front range and then spread out.  I don't mind seeing the core of the cold at the northern border of the US.  If that cold air mass is real, it likely verifies at about the latitude of roughly Chicago IMHO.  Not sure @John1122 can take another snowstorm in New Orleans.  LOL!

Just now, TellicoWx said:

Yeah the teleconnections for that time frame has been interesting, think the OPs are starting to clue in. Even with a neutral/slight + AO..a crashed EPO can buckle the cold south...sprinkle in blocked pattern over the Atlantic to slow an system's and things should be interesting. Temps here normally lag the crashing EPO by a few days (unless the PNA doesn't cooperate).

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PSU in the MA thread mentioned that if you look at the 850 temps on the Euro, it is moving towards the broad trough idea.  Bob Chill and FRD talk a little (they were just throwing it out there...not a forecast and more just fun speculation...forgive me if that is wrong!) about how an overrunning event could be derived from that broad trough look on the American model.  I tend to agree.  Long way to go, but a fun set of model runs, especially considering that modeling looked awful several days ago.  Definitely interesting.  

The 12z GEPS does offer a word of caution.  The EPO ridge gets so tall on it...that the GEPS tucks a trough under the big ridge.  So, that is the danger we need to be wary of in terms of the LR.  This actually happened last year.  Modeling went crazy for a cold East...and the trough tucked West.  I don't think the Nino will let that happen now that it is coupled.  However, there may be a window there for that to happen due to the IOD firing.  Long term, that tough likely gets kicked out of there.  Besides, park a 1050+ high over MT, and let's see what happens!  

1 minute ago, TellicoWx said:

12z Euro has trouble written all over it with a 1043 parked over the NE in a region with 1° temps at the end. CAD would be impressive with that setup 

Check out the thermal profile one the US on the GEFS after that.  But yeah, trouble written all over that pattern.  Pretty amazing shift in modeling during the past 48 hours.  I think the 12z GFS operational has a 1057 parked over western Canada on its run.  To me the GEFS is more impressive than the operational.  

End of the Euro run has extremely cold air entering northern Canada, spreading out, and head south.  EPS should be interesting.

I should note that the Euro is not at the range where the the other models hit some extreme stuff.  

Looks like the 12z GEFS supports the operational.  Now, all eyes turn to the Euro/EPS.  Euro through 204 is cold but less impressive.  The 12z GEFS is pretty cold for an ensemble. 

12z CMC is right there with it.  Wow, Canada gets cold on the GFS and CMC in a hurry.

Pretty funny to be talking about International Falls yesterday...and then the 12z GFS straight drops the hammer on the North Star State.  Source regions, anyone?  My favorite storm track is New Orleans/Mobile to inside Hatteras.  The track(take with a huge grain of salt) on that GFS run would be a close second and an old school one at that.  Again, crazy we were just talking about that yesterday.   

Got a little band of snow over eastern Hawkins and western Sullivan.  Super narrow, but snow nonetheless.

And today’s winner is the 18z GEFS temp anomaly map!