December 8-10 Storm Discussion

[TellicoWx]

3 minutes ago, Carvers Gap said:

I think that is the conveyor deal that Jeff/MRX were talking about.  Basically, it catches the fetch off the Atlantic.  Not totally sure.  What do you think?  It comes out in such a weird fashion, I never know what to think?  

I think it revolves around where the 850 absorbs into the coastal, the further west it does like the NAM and GFS , it shuts the moisture feed down quicker and also has influence over pulling or slowing the coastal down. 

[Blue Ridge]

3 minutes ago, Carvers Gap said:

I think that is the conveyor deal that Jeff/MRX were talking about.  Basically, it catches the fetch off the Atlantic.  Not totally sure.  What do you think?  It comes out in such a weird fashion, I never know what to think?  

Looks like it to me. With systems that fail to make the turn, we often see the deform band "get stuck" on the west side of the Appalachians, even after snow has stopped over the western Carolinas. The band is usually just light snow, but often sticks around for a few hours after the bulk of the precip has passed. The most notable event I can recall was one of the two Christmas 2010 systems. 

[AMZ8990]

33 minutes ago, *Flash* said:

As mentioned by others on here, energy transfer and where it equates to Monday lift once the L is OTS will be key for middle TN. 12z GFS is encouraging. Icon not so much. FV3 is stuck on my end, but that precip shield @ 36 looks suspicious.

Edit: Per Wurbus, a dividing line look is sensible. The look in a vacuum confirms the itch to drive east early Sunday.

  The FV3 is trying to throw us a bone buddy!!  Big totals up your way for that run.  

[Carvers Gap]

5 minutes ago, TellicoWx said:

I think it revolves around where the 850 absorbs into the coastal, the further west it does like the NAM and GFS , it shuts the moisture feed down quicker and also has influence over pulling or slowing the coastal down. 

Probably is a combination of the two working in tandem...but that is about to get above my pay grade!  LOL

[TellicoWx]

2 minutes ago, Carvers Gap said:

Probably is a combination of the two working in tandem...but that is about to get above my pay grade!  LOL

Yeah I agree lol...if there is no cold supply, doesn't matter where it pivots.

[Blue Ridge]

Looking at 850, the FV3 has it on top of HSV at hour 72. At 75, it appears to begin transferring. The kicker is that 850 winds are howling across NE TN from the SE or SSE from hrs 75-84. At 87, they have turned ESE. As Math/Met mentioned yesterday, we need a more easterly component to the winds to stave off as much downsloping as possible. 

 

Addendum: the FV3 has been quite consistent for NE TN.

[TellicoWx]

5 minutes ago, Blue Ridge said:

Looking at 850, the FV3 has it on top of HSV at hour 72. At 75, it appears to begin transferring. The kicker is that 850 winds are howling across NE TN from the SE or SSE from hrs 75-84. At 87, they have turned ESE. As Math/Met mentioned yesterday, we need a more easterly component to the winds to stave off as much downsloping as possible. 

Honestly I'm not quite buying what the FV3 spit out. You would think and approach into NW GA like that would shoot the 850s up the valley, plus the natural warming downsloping plays. If it approached from as sw to ne from central AL into NE GA, then yeah it would funnel the cold down the valley.

[Blue Ridge]

Honestly I'm not quite buying what the FV3 spit out. You would think and approach into NW GA like that would shoot the 850s up the valley, plus the natural warming downsloping plays. If it approached from as sw to ne from central AL into NE GA, then yeah it would funnel the cold down the valley.

I agree that it looks a bit odd. It looks like the energy splits as it’s transferring, with a piece traveling NW of Chattanooga.

I don’t think an 850 low on its trajectory (prior to the split) would result in what the FV3 is showing.

[Carvers Gap]

Added in the UKMet and FV3(non inflated...eastern valley...coudn't find the entire state) accumulation map links(SE forum) to my post above....

[John1122]

My area has really taken a nosedive in the last 12 hours. Lordy. This will go down as the biggest model swerve I've ever seen if the 12z suite is correct and their trend continues. It's probably going to change how I approach the weather hobby as it is essentially pointless to even check a model outside of 48 hours for the Valley region if you want more than a general idea about the pattern at 500.

[Carvers Gap]

12z Euro is rolling...

@John1122, I agree that following a storm from d7 is probably not the best unless a big signal like this one.  Hopefully this winter(next round looks like late Dec/early Jan), we will have enough to track so that the LR is not so tempting to delve into.

edit:  check that...forgot about the threat later next week.

[Carvers Gap]

Through 24, slightly stronger push of cold over the top near KY.  That has usually been a good indicator if the run will be flatter or steeper.  

[John1122]

1 minute ago, Carvers Gap said:

12z Euro is rolling...

@John1122, I agree that following a storm from d7 is probably not the best unless a big signal like this one.  Hopefully this winter(next round looks like late Dec/early Jan), we will have enough to track so that the LR is not so tempting to delve into.

I  expect t to pretty much end things for my area. Good luck to everyone in NETN/SWVA. Hopefully the NAM can somehow be true for the folks out west as well. 

 

[Carvers Gap]

Through 36, the hp has pushed slightly further south.  

[ShawnEastTN]

My area has really taken a nosedive in the last 12 hours. Lordy. This will go down as the biggest model swerve I've ever seen if the 12z suite is correct and their trend continues. It's probably going to change how I approach the weather hobby as it is essentially pointless to even check a model outside of 48 hours for the Valley region if you want more than a general idea about the pattern at 500.

You will get something and likely plenty of it you are in a much more favorable location than us in the great valley. You have much to be optimistic about.

Sent from my SM-G965U using Tapatalk

[Carvers Gap]

Through 42, the Euro is ever so slightly north with precip.  Just eyeballing, this run still may be a tad flatter than 0z.  

[Carvers Gap]

@60, high pressure appears to be making its presence knowns as precip is ever so slightly south now.  Very similar to 0z so far.

[Carvers Gap]

At 72, snow moves into NE TN.  Very little divergence from the 0z run to this point.

[John1122]

The Euro will probably end up very similar to the UKIE by the look through 72.

[Carvers Gap]

By 80, the snow is back into Knoxville w mix all the way back to Nashville. By 84, looks a bit juicier than 0z.  Almost the same run as 0z.  Some expected downscoping present.

[John1122]

The Euro was about the same as 0z at the end, but it cut everything almost west of the northern highland rim except a dollop around or just west of Nashville. Complete polar opposite of the NAM with it's heavy snow in N/NW Tennessee.

[Carvers Gap]

1' totals along the KY/TN boarder and NE TN/SW VA.

[John1122]

It was better in the Knox area than 0z. Looks more like the EPS from 0z there.

[Carvers Gap]

Light snow at 96 across much of the eastern 2/3 of the state.  

[BlunderStorm]

28 minutes ago, John1122 said:

My area has really taken a nosedive in the last 12 hours. Lordy. This will go down as the biggest model swerve I've ever seen if the 12z suite is correct and their trend continues. It's probably going to change how I approach the weather hobby as it is essentially pointless to even check a model outside of 48 hours for the Valley region if you want more than a general idea about the pattern at 500.

I share your sentiment with this. Though I am still staying optimistic.

[John1122]

For some reason I thought it warm nosed Knoxville last night, but it did not. So it's virtually a mirror image of last night's run but it cut back on some of the 1-1.5 inch totals out west.

[John1122]

2 minutes ago, BlunderStorm said:

I share your sentiment with this. Though I am still staying optimistic.

You're probably in the best area of anyone who regularly participates in the forum for this one. The fellow from Bluefield who posted yesterday will almost assuredly get 8-12 inches as well. Bluefield is one of the snowiest cities in the VA/WVA region it seems like.  I remember the local forecast on TWC back in the 80s always had Bluefield as one of the regional cities and it seemed like their obs said snow in winter almost every day.

[Mountian Man]

1 minute ago, John1122 said:

You're probably in the best area of anyone who regularly participates in the forum for this one. The fellow from Bluefield who posted yesterday will almost assuredly get 8-12 inches as well. Bluefield is one of the snowiest cities in the VA/WVA region it seems like.  I remember the local forecast on TWC back in the 80s always had Bluefield as one of the regional cities and it seemed like their obs said snow in winter almost every day.

Even though that 8 to 12 is good for us. That is the normal here. Lol

[Carvers Gap]

Going to give this a look more closely.  Amounts over SE KY increased significantly.  So the storm backed a bit.  Likely means the slp turned the corner over the coastal plain more at the end of the run.  Every bit helps if it gains latitude once east of the area.  That is a good trend.  Her is the WxBell map.  Thanks to @John1122 for posting the earlier map.  

 

[John1122]

2 minutes ago, Carvers Gap said:

Going to give this a look more closely.  Amounts over SE KY increased significantly.  So the storm backed a bit.  Likely means the slp turned the corner over the coastal plain more at the end of the run.  Every bit helps if it gains latitude once east of the area.  That is a good trend.  Her is the WxBell map.  Thanks to @John1122 for posting the earlier map.  

 

The Euro doesn't see as much downsloping for the NE so that's good. The gradient over Knox is the gradient that is over my area on the CMC. Right now it's the FV3/Euro vs the rest regarding snow in Knoxville.