Clinch Leatherwood

Forecasters so often tend to only look forward, seeing each model run as a reset.  That's what happened with the Euro.  Each time it shifted NE someone on the edge to the NE justified it as okay, ignoring the shifts because it's the euro and always right.

The simple clown Euro Wx snowfall maps, taken all the way back from the 1/24/0z run forward provided a fascinating and undeniable animation    With a  relatively stable model like the Euro it's IMO extremely useful to look at those generic, quantifiable summary type trends to see what the model is doing and moving.  Particularly with the snowfall clown map it kind of gives a rough look at temps, QPF etc which can give a very quick snapshot.

It's useful with the GFS as an offset to the Euro too, but the NAM...forget it. 

I asked on the NYC thread too.....why did NCEP/HPC summarily and repeatedly dismiss the RGEM/CMC?  It appears this was done simply because the Euro carried so much weigh the other way, it was discounted. 

lol some of us just will, stay up and watch this debacle back this way. You know over the past couple days I would get annoyed with your analysis but I have to hand it to you. You nailed this system with the eastern capture two days ago and that this was really just a ene event. Well done man, for real.

Appreciated but like I said aside of Kevin/Steve/Will's death band....it was mainly macro.  I still cannot really see why it failed or why it's done this a couple of times now.  DT says it's the 50/50 being over modeled, Ocean had the good find on the digging s/w.....who knows?  It never had these issues before the upgrade. 

This is the my March 2014 heart break that will change a lot of people going forward when the Euro stands alone on the sw/slow edge of guidance (until they fix).

FWIW, I may blow this yet.  I really don't buy the widespread nature of the Euro totals overnight, nor it's all day snows tomorrow and I stand to get croaked the most by OES.   I may be wrong as this issue may dampen in a mature storm setting.

BUT, I see the w/v and radar down to the s/w and clearly we're seeing something take place as the "support" seems to be going over the top of that band (note it's building behind it to the east now)....

http://radar.weather.gov/radar.php?product=N0R&rid=okx&loop=yes

I am guessing about another 8-12" here.  Snow winds down by 11 or 12.

No question the long duration aspect of this storm is now somewhat in doubt. I honestly do not think anyone outside of SE MA or where the fronto band stalls out is going to get >24". It is obvious at this point where things are trending.

For those so inclined http://www.wunderground.com/wundermap/?zoom=4&rad=0&wxsn=0&svr=0&cams=0&sat=0&riv=0&mm=1&mm.mdl=GFS&mm.type=SURPRE&mm.hour=0&mm.opa=100&mm.clk=0&hur=0&fire=0&tor=0&ndfd=0&pix=0&dir=0&ads=0&tfk=0&fodors=0&ski=0&ls=0&rad2=0

Flip between the 12z and 0z.  Worst I've ever seen the Euro do.  That's pathetic for that time range, if it were the NAM it'd be getting crapped all over.

Now here's the thing?   How do we know it's not off by just as much at h12 this run?

Food for thought..although radar looks good.

Lot of people going to wake up very pissed off to the west.

Looks like the band is not far from it's maximum push west.   Gaping hole in RI.  What's up with RI and sucker holes?

what an epic fail for the Euro, especially for western folks

 

It's go-time and the Euro jumped almost 100 miles east in farthest QPF extent in 1 cycle

One thing about the team behind the Euro.  They'll figure out what's happened since the upgrade and probably fix it next update. 

Clinch Your the man on this storm

 

I have seen you nail another storm like this

 

Well done man, well done

Thanks but like I said more about going through this twice last winter with storms stalling further east (nobody else cared)..and it did this than having any unique insight.  More a grudge!

Agreed!  I've been a fan ever since he nailed a March 2005 storm.  Hard to believe it's been a decade. 

That was one to remember too.

Too many chefs in the kitchen with this storm... and the models struggling to figure out which chef is the head.

 

Any posters in Clinton CT cashing in on that?

No -NAO, seems to be the case that we don't get things to come together as easy. 

It's going gong show now, look at that moisture exploding in the old dry slot.   Also note the screw zone developing in between the two main bands.   Something to watch.

what an epic fail for the Euro, especially for western folks

 

It's go-time and the Euro jumped almost 100 miles east in farthest QPF extent in 1 cycle

What hasn't changed is the max jack zone staying near Boston/PVD.  Multi-model consensus on that, so perhaps the error minimizes/mutes once the low is more mature.  Who knows.  I do plan on an earlier exit to the snow tomorrow, probably before lunch for the serious stuff aside of some bands or OES.

Really getting cranking now, moisture just piling in from the SE

Stall is nowhere near what it was on 12z Euro.

 

Not only is SLP further east, the rapidity of exit is greater:

It's like 30 miles east at 18z Tuesday, then by 0z Wednesday it really starts to move away about 60 miles northeast.

Also, the spoiler low starts off southeast of the low we had on the 12z Euro, but eventually is much further northeast.

 

Upsetting for lots of folks I'm sure.

For eastern MA, hope we do well on a deformation band which now seems to be ours.

When does it stop the error?   We appear to be about to see a split with one deform band to the west, another near the coast and then some OES. 

Talk about a coup for James way out there on the Cape

 

Starting to look like Boston metro does well because it's in the deformation band

 

The real blow comes between 6z and 12z... the dual low structure collapses on the east-most low, whereas at 12z it collapsed in the west-most low. And as Messenger discussed, less of a capture, the east-most low scoots out faster once it takes over.

the Euro is no longer infallible and has a particular issue with negative tilted east coast troughs/captures absent true -NAO. I would call it a clear bias at this point, there are enough instances since the upgrade to document.    It's 10 plus year dominance did a p diddy mind f&&& on people up an down the coast.  Still the best, but perfection is no longer guaranteed.   

Further east towards the RGEM?

Impossible to know,  but I would take whatever the Euro shows from this run right now for 12h, and adjust it based on the last 5-6 runs worth of trends.

I don't think the HRRR looks terrible, and I will say at this point I doubt widespread meanginful snow after lunch in EMA.  I think bands sure, but I think it'll continue possibly to be displaced ENE.

Also - was saying to steve and kevin earlier...I thought the jack zone may be in their triangle with Will.   Can see an explosively developing band there.  May not go far.  That could be a secondary jack that the HRRR etc are picking up on .

Yeah, That is a very good hit, Do you have qpf numbers brian?

For this run.   I think at this point we have to once again assume it's struggling to ascertain the development and adjust this run, and our expectations accordingly.

Euro caves east...still much more impressive with the precip extent than the RGEM/GFS, but it def caved east.

I will stand by what I said, against itself this is one of the poorest performances I can remember for the Euro.  Luckily semi-predictable and I do think we're beginning to document a bias, JMHO.

If history is a guide the Euro is not done catching up. 

Wxniss I meant to post this on this thread...but the HRRR (not a fan) starts to come apart soon too.  This was the 3z total snow output.

BTW 12z Euro had the same feature along the boundary...it just collapsed hardest and fastest to a position under ack. That can should flip hard east or SE S in the next few hours if those west tucks are valid.  If we see it staying E or ENE or NE....we very clearly know the low is staying further east.

Nowcasting at it's best, with relatively big stakes on the line.

Over next 2 hours, will be watching SLP, pressure fall rates, strength of the western CT / Long Island band and backfill of echos into NYC/NJ. And of course let's hope Euro can keep some respectable continuity right at showtime.

This sticks out to me  http://www.ndbc.noaa.gov/station_page.php?station=44008

I do think this lends some credibility to at least a temporarily extension.

Clear on water vapor, but so far doesn't seem to have translated to an elongated or dual surface low:

 

pres.ne-large_12am.png

 

Biggest Euro vs. RGEM difference in this regard occurs between 6z-9z when RGEM really develops a 2nd low way out, like 67W, whereas Euro collapses everything into one consolidated low. So as you and others have said, the evolution now to 4am will be critical.

GFS hints at it, but then collapses everything back again.  UKMET hints at it, collapses back too on the western edge. NAM never really bites at all.

Looking at the WV though...I do think wxniss we'll see a pulse down center to west for at least a few hours, as we wait for the rest of the energy to dive and for it all to stack.   We'll see what the radar shows in central/wMA,   CT, LI and sw in the next hour.

Why would NWS still be sticking to their guns on totals?

Lack of any clear and convincing reason to change for another few hours.

You can see wxniss found a good point there....The RGEM spins that up, and in the next 3-5 hours elongates the low NE from the benchmark.  It's at that moment the dynamics begin to whither a bit aside of some deformation banding. 

The GFS and NAM don't do this, nor does the 0z UKMET.  If we see the radar go to dogsh* from SW to NE the further west and south you guy starting about 1-2am aside of some bands....we'll know there's a potential issue. 

It should be clear as day in the next 1-2.5 hours.  We'd see a pretty marked decrease in intensity of even the banded snows off the NJ coast up through LI and into C W MA.  GFS/RGEM are not terribly dissimilar the GFS just doesn't bite on the elongated low.  NAM is on it's own right now.

Everything is wrapping up. Very marked increase in winds, very notable spin now to the radar.  Maybe a few gravity waves south?

The RGEM was too far east even initially-good snow really was never supposed to make it past Islip and it's now entering NYC and still going. To me the storm still looks very potent aloft and should at least slow significantly for a while. I'm becoming more cautiously optimistic that NYC shares in some of the high totals, as does W CT/MA. Maybe even NE NJ but the band's progress is really slowing now.

This is a theme I've been beating since Saturday... RGEM has an intense piece of vorticity far northeast of any other model, approximately near the Cape. At times in the past 2 days, this has resulted in a dual-low system (and GGEM did this too on Saturday). And I think it's now contributing to this further and faster northeast scoot.

 

May be totally wrong, but don't have access to Euro H5 to get a better sense of the responsible mechanics. 

 

The other mechanism that I keep beating: it's not just an eastward tick of a single SLP placement, I think it's also a northeast-stretch / dual-low-ish structure that is robbing some of the feed that would otherwise get pivoted west.

 

This actually may be the biggest fly in the ointment that the RGEM presents to the historic potential... and it's not on the EURO. Big difference. Something to watch for.

 

rgem_precip_mslp_neng_4.png

You can see that eastern lobe clear as day on the water vapor, I have no doubt there's at least a kink under it.

You know I live just SE of him. Flakes are just being demolished though

How is your snow rate?

The stall aspect is a tough forecast. New 03z RAP stalls it now more like the NAM vs the more progressive solutions.

 

I'm not quite sure what to make of the differing model solutions on the stall aspect for tomorrow afternoon. My gut says you are staying in good snow most of the tomorrow and into the evening.

Thanks.   Whatever the RGEM is doing - it happens in the next 2-3 hours.  It is tucking everything nicely and I believe as the radar and WV show right now through about 7-8z...and then it just loses it and becomes progressive.

Its gonna be tight for NYC, my hunch now is it will make it and stall just west of them the stuff off NJ is slowing its west progress which likely means we'll see the west progress slow up north within 1-2 hours.

Exactly.  I think you absolutely found the Achilles heal in that 12z Euro run, that would obviously have slowed the progress N & E of everything and changed all sorts of things.  Curious for it to have that type of issue with the superior schemes it uses for init.   My big concern now is not losing the positioning during the day that allowed for a constant feed of moisture into eastern ma

Meanwhile Kevin is getting tatoo'd in Tolland by that persistent band.

Euro had steady snow well back into all of NJ by now...all the way to PHL. It's going to be too far west...there is zero doubt in my mind. The question is by how much.

Exactly. I doubt West Milford etc is going to lay down another .25 or so in the next 75 minutes.  Tonight is not in doubt, people forget at one time we had some form of snow going into Wednesday morning.  RGEM it's mainly over by lunch.   Really want that to be wrong.  If the Euro leaps ENE in the eventual stall the super historic totals are gone.  Who cares, it's a great event.

I don't think it makes a ton of difference in E MA to be honest...it might reduce the chance of mixing with rain on the outer Cape.

Will - my primary concern is early morning through tomorrow.  The historic nature of this event came from the frosting on the top during the day and into the evening. If the RGEM is right that's not happening (and UKMET).  GFS and NAM both made significant leaps east from their previous runs.    We shall see, going back out to enjoy.

Look away from the UKMET....

It's way wrong with the precip near NYC. Look at how light it is. There is a deform band on the city's doorstep as we speak.

We will see, the band isn't making tremendous landward progress off ACY...it still is further north, and the RGEM very clearly leaves it a little west of where it is now for several hours overnight. I mean it's clearly there on the model, but it also lifts the stuff aligned WNW to ESE towards SNE.   Hey maybe in 90 minutes I'll be totally wrong....

I believe euro will end up being largely right. Nj not far from getting into the action. To say this is a terrible euro performance to me is ludicrous. It trended appropriately. But unlike the others didn't bounce around with huge swings.

I said it would be one of the poorer euro performances.  I'll stand by that in general, I think it'll continue shuffling, but i'm hoping this RGEM quick exit is very much an error.  That'd su(k tomorrow.

Sbos,  how is this grievously wrong?  It may have slightly underdone the strength of the one band over western LI but the edge of where it'd be is kind of well defined.  It's also picking up on the expanding area of moisture I think every well..coming up from the south.

What am I missing that you are so clearly seeing?

I think that's the way you have to play it right now.

 

It is the Euro, which gives you some pause, but if this was any other model that far west and juiced it would be tossed.

 

This will go down as one of the Euro's poorer performances.  Ultimately what NCEP kept noting on it being too slow vs the other models continued to bite its' forecasts.   I'm hoping the CMC products are missing something and are kicking the low NE too fast in the morning.  NAM and GFS are very nice. 

Looking at the WV and analysis, at least through it's first 6-12 hours I really like the 0z GFS.

You're a lot better at picking up on these little nuances than I am, which is why I definitely keep tuned to your posts, and you called the Euro as being overdone right away and it looks very much like you'll be right. I still regard the Euro quite highly but it definitely punked lots of people west of NYC. 

 

I'm done with models at this point-right now it's all about the obs and radar, which IMO look good at least to NYC and the NJ shore. Hopefully the band coming out of Suffolk County can sit over those guys and pivot for a while. I feel bad for those who get stuck west of that-amounts might be 1/3 of what occurs in that western band. That's always a doozy.

It's not anything I picked out from watching the last few days (other than the first jump it made occurred right in that 42 hour ish window where it seems to start).   If I hadn't suffered through those two non-events that only James and I cared about anyway...I wouldn't have been as persistent.   I really do believe late today and tonight it was really obvious the Euro may have been in error.  And the WV right now has me even spooked for "historic" here as it could well be winding down at lunch tomorrow.

I can't justify tossing the RGEM....the epic duration of this one is in doubt.

These storms are always a nailbiter for NYC-Boxing Day was really the exception and wasn't even a classic Miller B like this one. 2/8/13 closed off and bombed just a hair too late and blew up over Long Island. 12/30/00 nailed everyone but rained on Long Island. This one I still have a good feeling about-the bands still have good momentum west and are already coming into E NJ. Nassau and Suffolk Counties are still in a very good spot. Obviously you guys are mostly laughing about all this but for Upton and Mt. Holly it's a hair-puller since these 40 mile differences impact perhaps millions of people. Philly I think is in big trouble for anything more than 4-6" at this point-Mt. Holly had them at 10-14" on the maps. 

 

This is how Miller B's that blow up from clippers always behave, notwithstanding exceptions like 12/30/00 and Feb 1978, but some probably bit too hard from NYC to PHL. 

above my pay grade...but I think there's something with the new version of the Euro that just can't get the physics down on where these things are going to stall.  It's the same bias every single time and I've only noted it since the last big upgrade.  Same direction, multi-run starting at about 42-48 hours from the event whether it picks up the event  at 120 hours or 72...same drill.  Meanwhile RGEM seems to actually do fairly well at least this last 15 months being more progressive.  The others seem to offer no real consistency at all, and the GFS is ALWAYS most east.

Meanwhile 0z RGEM definitely east of the 12z early.