March 5-6 Storm Discussion

[CaryWx]

I hope it comes back south some, I would love to see everybody get in on the action... That said I wouldn't bet on much if any southward trend... I trust the Euro much more than GFS, but that don't mean Euro is right GFS is wrong. But I would give Euro more weight on this, I read somewhere that it usually does best on big east coast storms? What we don't want to see is the Euro tick north at 0z that to me would be a BAD sign for NC folks!!! 

Exactly. Hold serve or wobble south. 'fraid it will follow though.

[CaryWx]

Why does it seem a southern track is always dryer though, ergo no real bomb/windup

[tarheelwx]

Really it's amazing how consistent the models are this far out. How could you be more certain of 12"+ imparts of va when you're still 84 hours out?

[WilkesboroDude]

Storm Scenario Number 1, Track & Impacts

As the storm reaches the East Coast, we now have two potential scenarios. The first sends the storm eastward off the mid-Atlantic coast, leading to a substantial snowstorm from the central Appalachians into the western half of Virginia, western Maryland and the high spots of western North Carolina.

 

 

Accu weather still thinks there is a chance of the southern track.

 

Map and text is way off for the South.

[SeVa]

Saw this from NC Piedmont Weather on facebook. It's not a foot, but all I have said from the start is I wanted at least a half foot of snow. I would be very happy with this.

What are this guy's credentials? Is he a met?

[CaryWx]

Really it's amazing how consistent the models are this far out. How could you be more certain of 12"+ imparts of va when you're still 84 hours out?

Isn't that the telling thing though? Consistency I mean. Tells me the modeling overall has this thing pegged

[superjames1992]

The 12z UK Met was pretty far south.  Just something to consider...  No need to throw in the towel or cancel winter yet.

[tarheelwx]

Isn't that the telling thing though? Consistency I mean. Tells me the modeling overall has this thing pegged

I agree. While 50 mile wobbles at this range is to be expected, such wobbles are magnified by the dramatic accumulation gradients.

Tw

[Tacoma]

Map and text is way off for the South.

they probably meant wnc period. looks like maybe even extreme upstate.

[Marion_NC_WX]

Robert just posted a video for his subscribers...big update in regards to the storm and I'm thinking its his first call.

[BIG FROSTY]

The 12z UK Met was pretty far south.  Just something to consider...  No need to throw in the towel or cancel winter yet.

It's #2 behind Euro for accuracy, But you never here any Mets paying much attention to it,Why is that?

[packbacker]

It's #2 behind Euro for accuracy, But you never here any Mets paying much attention to it,Why is that?

 

I was thinking the same thing but all we have access to for upper air modeling on the UK is all inside 72 hours.  So 12z tomorrow it will be useful.

[griteater]

I think everyone from NC south would like to see this trend south. I have no idea whether that is likely to happen or not (my gut says no, but whatever) but can someone give any thoughts as to what we should look for that would be a catalyst for a south trend to occur? Stronger blocking? Better 50/50? Stronger system? Weaker system? Energy in the southern stream weaker, slower, not there? Sharper ridge out west? What?

Why does it seem a southern track is always dryer though, ergo no real bomb/windup

 

Cold Rain, my take is that we want to see the location of the max confluence locate itself farther southwest.  The upper low has to track underneath the area of max confluence that is located to its northeast as it treks along.  So, how we get that confluence located farther southwest isn't as important...it just needs to get there...could be that the NE trough / 50-50 low is stronger, could be that the NE trough / 50-50 low is located farther southwest, could be that the amplitude ahead of the upper low is weaker...or a combination of all three.  I also don't think the western ridge behind our upper low is getting enough play here.  I mean, a ridge building behind a wave digs it farther south, right?  By comparison, the March '09 storm that dug deep into Georgia had stronger ridging behind it - http://www.meteo.psu.edu/~fxg1/NARR/2009/us0228.php

 

CaryWx, you touched on something that I've thought about as well.  In the SE, whenever we have a super suppressed storm, most of the time it is rather weak (notable exceptions being Feb 1973 & Feb 2010).  So, not only do we have to get it to trend north, we have to get it to amp up stronger as well. In contrast, the folks in DC are watching bombs go off to their south on the models, and all they have to do is wait for the storm to creep north...but all of this leads to the Surf and Turf taste that comes when we do land the ever elusive widespread snow bomb across the southeast.

[CaryWx]

Cold Rain, my take is that we want to see the location of the max confluence locate itself farther southwest.  The upper low has to track underneath the area of max confluence that is located to its northeast as it treks along.  So, how we get that confluence located farther southwest isn't as important...it just needs to get there...could be that the NE trough / 50-50 low is stronger, could be that the NE trough / 50-50 low is located farther southwest, could be that the amplitude ahead of the upper low is weaker...or a combination of all three.  I also don't think the western ridge behind our upper low is getting enough play here.  I mean, a ridge building behind a wave digs it farther south, right?  By comparison, the March '09 storm that dug deep into Georgia had stronger ridging behind it - http://www.meteo.psu.edu/~fxg1/NARR/2009/us0228.php'>http://www.meteo.psu.edu/~fxg1/NARR/2009/us0228.php

 

CaryWx, you touched on something that I've thought about as well.  In the SE, whenever we have a super suppressed storm, most of the time it is rather weak (notable exceptions being Feb 1973 & Feb 2010).  So, not only do we have to get it to trend north, we have to get it to amp up stronger as well. In contrast, the folks in DC are watching bombs go off to their south on the models, and all they have to do is wait for the storm to creep north...but all of this leads to the Surf and Turf taste that comes when we do land the ever elusive widespread snow bomb across the southeast.

Yes and unfortunately all I can add is climo and geography. It just gets us down here in the good south.

[Buddy1987]

Great mid Atlantic crew already talking about the 21z SREF looking great for south central PA

[Buddy1987]

NAM has initialized! Out to 15

[CaryWx]

This'll be a Hudson valley storm before long

[Cold Rain]

Cold Rain, my take is that we want to see the location of the max confluence locate itself farther southwest. The upper low has to track underneath the area of max confluence that is located to its northeast as it treks along. So, how we get that confluence located farther southwest isn't as important...it just needs to get there...could be that the NE trough / 50-50 low is stronger, could be that the NE trough / 50-50 low is located farther southwest, could be that the amplitude ahead of the upper low is weaker...or a combination of all three. I also don't think the western ridge behind our upper low is getting enough play here. I mean, a ridge building behind a wave digs it farther south, right? By comparison, the March '09 storm that dug deep into Georgia had stronger ridging behind it - http://www.meteo.psu.edu/~fxg1/NARR/2009/us0228.php

CaryWx, you touched on something that I've thought about as well. In the SE, whenever we have a super suppressed storm, most of the time it is rather weak (notable exceptions being Feb 1973 & Feb 2010). So, not only do we have to get it to trend north, we have to get it to amp up stronger as well. In contrast, the folks in DC are watching bombs go off to their south on the models, and all they have to do is wait for the storm to creep north...but all of this leads to the Surf and Turf taste that comes when we do land the ever elusive widespread snow bomb across the southeast.

Thanks Grit. We'll see if the block comes in a bit stronger. Maybe that can help with the 50/50. The stronger ridge makes sense too, but with that big storm coming into the ridge (there's your snowstorm-killing Pacific, Bevo), I wouldn't count on that amping up. We'll see shortly.

[Cold Rain]

Great mid Atlantic crew already talking about the 21z SREF looking great for south central PA

Gonna be funny when New England gets another 2'.

[Tacoma]

This'll be a Hudson valley storm before long

something isn't right trending north to much, to me this is a red flag.  just heard another very reliable source that says this can't go north much more than va because of the blocking.  he said its not going to happen.  this is about the 3rd of 4th met i've heard and read say this.  va is probably game on and maybe nc but if the blocking is stronger it can only go south some and out to sea.

[Buddy1987]

Only thing I can see so far out to 21 is the energy instead of being over SW Montana is on the northern Montana Canadian border

[NC_hailstorm]

It's #2 behind Euro for accuracy, But you never here any Mets paying much attention to it,Why is that?

HPC uses it,here's part of their heavy snow discussion today.

 

 

THERE CONTINUES TO BE ENOUGH VARIABILITY BETWEEN THE MEANS AND THEOPERATIONAL RUNS FOR CONTINUED UNCERTAINTY BUT THE OVERALL HVYSNOWFALL AXIS OF THE NRN PLAINS/UPPER MIDWEST TO MID MS VLY/WRN OHVLY APPEARS QUITE CERTAIN. HPC FOLLOWED A MULTI-MODEL BLEND FORSUN... THEN A ECMWF/GFS COMPROMISE FOR MON BEFORE FOLLOWING THEECMWF AND UKMET COMPLETELY FOR TUES. THE TRANSITION FROM MON TOTUES AND REASON FOR THIS MODEL CHOICE IS THE GFS TRENDING TOWARDTHE ECMWF ON MON AND THE NCEP GUIDANCE ALLOWING TOO MUCH QPF/FOCUSIN THE COLD SECTOR... SOMETHING THE ECMWF AND UKMET SEEM TO STRAYAWAY FROM VERY WELL.

[Buddy1987]

Looks pretty similar to 18z at 30 hrs referring to h5

[BIG FROSTY]

HPC uses it,here's part of their heavy snow discussion today.

 

 

THERE CONTINUES TO BE ENOUGH VARIABILITY BETWEEN THE MEANS AND THEOPERATIONAL RUNS FOR CONTINUED UNCERTAINTY BUT THE OVERALL HVYSNOWFALL AXIS OF THE NRN PLAINS/UPPER MIDWEST TO MID MS VLY/WRN OHVLY APPEARS QUITE CERTAIN. HPC FOLLOWED A MULTI-MODEL BLEND FORSUN... THEN A ECMWF/GFS COMPROMISE FOR MON BEFORE FOLLOWING THEECMWF AND UKMET COMPLETELY FOR TUES. THE TRANSITION FROM MON TOTUES AND REASON FOR THIS MODEL CHOICE IS THE GFS TRENDING TOWARDTHE ECMWF ON MON AND THE NCEP GUIDANCE ALLOWING TOO MUCH QPF/FOCUSIN THE COLD SECTOR... SOMETHING THE ECMWF AND UKMET SEEM TO STRAYAWAY FROM VERY WELL.

Thanks for posting that. Usually all you ever hear is Euro and GFS  till it get's with in NAM range.

[Buddy1987]

Nam stronger with the moisture field in Minnesota at 36 and def west with the energy in the upper Midwest hopefully this translates downstream.

[beanskip]

Only thing I notice through 42 is the southwest s/w is a bit weaker, so our main low is more positively tilted -- this goes to WeatherNC's point about the secondary low that spins up in the Ohio Valley.

[Buddy1987]

Not good with picking up on confluence in New England but it seems a little stronger? Would need someone to chime in on that however because I'm not 100%

[beanskip]

Blocking building in a bit better, but lately that doesn't seem to affect the track. To wit, this appears a bit north (again).

[tarheelwx]

Can anyone summarize Roberts video?

TW

[burgertime]

My problem with the NAM in the LR right now is what is always wrong with the NAM in the LR it has totally different looks every time. The worst part is even in the LR what the NAM is showing would be possible. I do though like that it seems that energy trying to race out in front on the southern side seems to be weaker with each run in the short range.