Christmas Storm IV

[BIG FROSTY]

GFS gives me .24

I just can't believe what the TV mets are saying, They said MAYBE flurries back here in the N.Foothills ? Now I know I could get nothing, But what models are showing I can't understand why they are that down on the possibilty ?

[ST21]

Im a nervous wreck right now with the possibility of an inland track and with temps problems, also we may get dry slotted here in the central and eastern carolinas if it treks further west and inland.

here is good news. evaporational cooling will help you cool down. i dont think you will have temp problems but im just an amateur

[nchighcountrywx]

18z GFS: Lower I-73 corridor to NE part of state is winner on this run. Everything trails off quickly west of the I-73 line (west of Troy to Asheboro)

[buncombe]

It really isn't orographic enhancement but is enhancement caused by the inverted lee trough that usually develops with a low on the Georgia Coast. All the storms I've looked at that brought snow here, had that feature, including last seasons Feb snowfall, which was very tiny light flakes, but yet the enhancement stayed put. Once the winds went nw, the whole state evaporated of moisture, that takes a long time and this areas usually is about the last place to "snow out", next to the coast closer to the storm. Its always fun to watch the snow linger and linger a while even when the main low has passes to our northeast then suddenly it goes "poof".

Anyway the GFS is heading toward the Euro. It has all the main ingredients but what it does at 66 hours is start to erode the southern shortwave too quickly, then it kind of re-establishes it. Its trying to resolve how to handle it. I'm loving the looks of the northern stream.

One concern I think is legit is the potential for the storm to cut inland. Yes I know no model is showing it, but I'm leaving the door open to that simply because the extreme meriodonal (north to south) flow and deep anomalous trough that is incoming. We're in totally unchartered waters here I think, close to a 96 or 93, but different because of more blocking and stronger due north flow. Usually our big events have the trough coming in from the northwest this is almost due north when the sudden phase occurs, Therefore I won't be suprised to see the Euro step up its surface pressures a lot in the Northeast Gulf and southeast Coast. If the 5H cuts off from the mtns of NC or slightly west, its cause to pull the surface system more westbound than shown.

We'll see.

Well, we should get some orographic enhancement comes on the backside after the low lifts north!

As to the cutting inland, I assume that you would mean a track somewhere through the midlands of South Carolina (Columbia and points east).

[BullCityWx]

18z GFS: Lower I-73 corridor to NE part of state is winner on this run. Everything trails off quickly west of the I-73 line (west of Troy to Asheboro)

Trails off quickly? There's half an inch QPF all the way back to KGMU in SC...

[KChuck]

Appreciate the policing of the American board. It has been a lot cleaner reading and keeping up with events as compared to storm mode in the old Eastern board. Thanks mods!!!

Ok folks, let's stop with the small talk and one liners...it's getting to be a bit too much. There is another thread for that.

[lilj4425]

18z GFS: Lower I-73 corridor to NE part of state is winner on this run. Everything trails off quickly west of the I-73 line (west of Troy to Asheboro)

Not according to this:

http://raleighwx.ame...8zgfsp72102.gif That's total qpf from 18z GFS. Or do you just mean in North Carolina?

[phil882]

You can see how at 500mb that the 18z gfs is slightly further north with the southern stream shortwave, which allowed for an earlier phase, and a further north track of the surface low. This hurts people in the midlands of SC, but WNC/SC benefit the most, while the piedmont of NC still gets hammered. I'm currently writing and update to my outlook yesterday with a new map. I still won't go into detail about amounts, but I think its safe to say the Raleigh-Durham area is still looking very good.

[Carvers Gap]

The last Euro was the best solution for everyone involved. I know people from the Western/TN areas are worried, but the precipitation would surely be more expansive than depicted. I think areas of TN were even in the .25 range all being snow with okay ratios. I don't wish an OTS solution on anyone involved all the way to the NE coast.

This system will probably have a sharp cut-off on precip. Right now, NE TN looks to be on the wrong side of that cut-off. The GFS says otherwise. But who really buys the GFS since it came to the party like two days late - or more? It's like getting in a boat that is pointing in the right direction finally, but only because it's been spinning in circles. Eventually, it had to. As BlueRidge stated yesterday, if the ULL crashes into this area we could get decent snow. It looks less likely than yesterday. 0z models will be interesting to watch, as well as 12z, due to the system actually being on North American soil and having more/better data.

[Marion_NC_WX]

I've gone from NOTHING at 6z to .45 at 18z on the GFS.

The trend up this way was defintely good as well. We went from nothing on the 12z run to .28 on the 18z run and 850's starting at -4 and crashing to -8 before ending. In other words we have gone from nothing to high end Advisory criteria. The trend is our friend.

[Brian]

From FFC.

Statement as of 5:17 PM EST on December 22, 2010

... Wintry precipitation still possible from Christmas day through

Sunday morning for north and central Georgia...

A strong storm system currently moving across Southern California

and the Desert Southwest... will move into the Southern Plains Friday

and across the deep south Saturday and Saturday night... and bringing

a chance of wintry precipitation to much of north and central

Georgia. At this time all computer models are developing a surface

low over the northern Gulf of Mexico Friday night and Christmas

day... then moving the low across North Florida and off the Georgia

and South Carolina coasts by Sunday morning. This will begin

spreading moisture into the state beginning late Friday night and

continue through Sunday morning. If the current forecast timing and

track holds true... atmospheric conditions and temperature profiles

would support the initial light rain changing over to snow across

north Georgia by early Christmas afternoon... then changing over to

snow for most of central Georgia by late Christmas afternoon. Light

snow could continue across north and central Georgia Saturday

night... then gradually ending from west to east through Sunday

morning or early Sunday afternoon as the system moves up the

Atlantic East Coast. Current forecasted temperatures suggest

widespread 1 to 3 inches of snow accumulations may be possible...

and mainly for areas along and north of a Columbus to Macon line...

with isolated higher amounts likely across the north Georgia

mountains.

Anyone planning travel across north and central Georgia or the

southeast United States over the Christmas weekend should keep

abreast to the latest forecast on this developing winter storm

system.

[VeronicaCorningstone]

If the BUFKIT data I'm looking at is to be believed (from the Bufkit Warehouse site) for RWI, the 18z is a discouraging trend for those of us east of I-95 in NC. Big differences from the 12z to 18z. This west trend is making me very, very nervous.

[Tullioz]

GFS gives me .24

I just can't believe what the TV mets are saying, They said MAYBE flurries back here in the N.Foothills ? Now I know I could get nothing, But what models are showing I can't understand why they are that down on the possibilty ?

Still a big improvement from the 12z run which was 0. I went from 0 to .29 which is a step in the right direction.

[bingcrosbyb]

WRF @ 48 HR (end of run). Thought I would take a peek.

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/hiresw/12/images/hiresw_500_048m.gif

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/hiresw/12/images/hiresw_ref_048m.gif

[SBUWX23]

If the BUFKIT data I'm looking at is to be believed (from the Bufkit Warehouse site) for RWI, the 18z is a discouraging trend for those of us east of I-95 in NC. Big differences from the 12z to 18z. This west trend is making me very, very nervous.

Not sure what your talking about.

[nchighcountrywx]

Trails off quickly? There's half an inch QPF all the way back to KGMU in SC...

I admit, I'm greedy. I want everyone to do as well as the High Country has so far this year.

I want everyone that has been left out the last few years in the lower western N.C. Piedmont to get 10+ inches! As we all know, a lot of .5 QPF is lost to moisten up the column and can end up being a 2'5" accumulation event.

[BullCityWx]

I admit, I'm greedy.

I want everyone that has been left out the last few years in the lower western Piedmont to get 10+ inches!

Me too bill, trust me. It's still a wsw event as depicted which is good enough for me.

[snowlover91]

If the BUFKIT data I'm looking at is to be believed (from the Bufkit Warehouse site) for RWI, the 18z is a discouraging trend for those of us east of I-95 in NC. Big differences from the 12z to 18z. This west trend is making me very, very nervous.

Not really, 850s are slightly warmer this run but that's all. Nothing to be concerned with right now, if the storm stays offshore we are fine. Main thing to watch is for an inland track which is possible but not likely. I'd go with a Euro/GGEM blend right now.

[SBUWX23]

If the BUFKIT data I'm looking at is to be believed (from the Bufkit Warehouse site) for RWI, the 18z is a discouraging trend for those of us east of I-95 in NC. Big differences from the 12z to 18z. This west trend is making me very, very nervous.

You must not be looking at RWI..

[strongwxnc]

All per the gfs... Would love to see a middle road with the euro's output here in WNC..

.34 here btw...

The trend up this way was defintely good as well. We went from nothing on the 12z run to .28 on the 18z run and 850's starting at -4 and crashing to -8 before ending. In other words we have gone from nothing to high end Advisory criteria. The trend is our friend.

[HWY316wx]

Posting from my phone so if this has been addressed please delete it.

The FFC is saying 1-3" from Columbus to Augusta with more for the mountains? Is this the strict GFS solution? To me the EURO looked like central GA and East GA were big winners not the mountains.

Or is this just the 3 day conservative post to give the tv mets the ok to put the run on Publix and Kroger?

[VeronicaCorningstone]

Not sure what your talking about.

http://www.meteor.ia...m/gfs3_krwi.dat 18z

vs.

http://www.meteor.ia...s/gfs3_krwi.dat 12z

Perhaps I'm reading them wrong or there is a data input issue. Dunno.

EDIT: AH - just refreshed the 18z. Evidently when I checked some of the data wasn't in, or something. At that point, it was showing a period of snow, then a short period of ice (@ 6 hrs) and then nothing for the rest of the storm. I knew it seemed odd, but I'm getting kinda giddy/nervous at this point. It's MUCH better now. My bad, y'all

[BullCityWx]

Bufkit gives rdu 11.5" this run

[Jaydog]

Us in eastern SC and NC need to hope for a slight southward trend and for it to be slightly more offshore so all the precip we get will be snow, id hate to waste precip on rain.

I doubt coastal areas are ALL snow in any solution. There in the Pee Dee is a toss up, but my thinking now is some rain, but likely a quick change over.

[WeatherNC]

If the BUFKIT data I'm looking at is to be believed (from the Bufkit Warehouse site) for RWI, the 18z is a discouraging trend for those of us east of I-95 in NC. Big differences from the 12z to 18z. This west trend is making me very, very nervous.

It gives you 18.8" of SN, compared to 6" on the 12z run. Look at your soundings (twisterdata) and thickness profiles (RaleighWX's model page), to get a better picture of implications of a slight westward shift. If an inland track were going to occur, I would expect to see at-least a couple ens members pick up on it, even 1. But the 12z GGEM and GFS members are all right along the coast, or for the majority, just offshore. As long as you are on the east side of the low by about 30 miles, you should be fine Veronica.

http://www.meteor.iastate.edu/~ckarsten/bufkit/data/cobb_gfsm/gfs3_krwi.dat

[snowlover91]

http://www.meteor.ia...m/gfs3_krwi.dat 18z

vs.

http://www.meteor.ia...s/gfs3_krwi.dat 12z

Perhaps I'm reading them wrong or there is a data input issue. Dunno.

Umm.. Your definitely reading it wrong. 12z shows 6" of total snow while 18z shows 18.8" of total snow

[WidreMann]

It really isn't orographic enhancement but is enhancement caused by the inverted lee trough that usually develops with a low on the Georgia Coast. All the storms I've looked at that brought snow here, had that feature, including last seasons Feb snowfall, which was very tiny light flakes, but yet the enhancement stayed put. Once the winds went nw, the whole state evaporated of moisture, that takes a long time and this areas usually is about the last place to "snow out", next to the coast closer to the storm. Its always fun to watch the snow linger and linger a while even when the main low has passes to our northeast then suddenly it goes "poof".

Anyway the GFS is heading toward the Euro. It has all the main ingredients but what it does at 66 hours is start to erode the southern shortwave too quickly, then it kind of re-establishes it. Its trying to resolve how to handle it. I'm loving the looks of the northern stream.

One concern I think is legit is the potential for the storm to cut inland. Yes I know no model is showing it, but I'm leaving the door open to that simply because the extreme meriodonal (north to south) flow and deep anomalous trough that is incoming. We're in totally unchartered waters here I think, close to a 96 or 93, but different because of more blocking and stronger due north flow. Usually our big events have the trough coming in from the northwest this is almost due north when the sudden phase occurs, Therefore I won't be suprised to see the Euro step up its surface pressures a lot in the Northeast Gulf and southeast Coast. If the 5H cuts off from the mtns of NC or slightly west, its cause to pull the surface system more westbound than shown.

We'll see.

After looking at the reanalysis for '93, I think it'd be unlike for it to cut too much further west. The PNA ridge is a lot further east (over the Rockies/Colorado instead of the west coast) and the models have been pretty consistent about that. So it seems like that would limit how far west the phase would be able to take place. Furthermore, the 50/50 low and ocean low are a lot stronger than what there was in '93, where there was already ridging out of ahead of the storm a day or two in advance. '96 is even worse of a match with a much different pattern leading up to the storm and, again, a phase much further west than looks like could be possible with this set up.

[packbacker]

http://www.meteor.ia...m/gfs3_krwi.dat 18z

vs.

http://www.meteor.ia...s/gfs3_krwi.dat 12z

Perhaps I'm reading them wrong or there is a data input issue. Dunno.

All I see is 19" of snow with the 18z :-).

[SBUWX23]

http://www.meteor.ia...m/gfs3_krwi.dat 18z

vs.

http://www.meteor.ia...s/gfs3_krwi.dat 12z

Perhaps I'm reading them wrong or there is a data input issue. Dunno.

EDIT: AH - just refreshed the 18z. Evidently when I checked some of the data wasn't in, or something. It's MUCH better now.

Look at the ratios!

[Weather Czar]

It gives you 18.8" of SN, compared to 6" on the 12z run. Look at your soundings (twisterdata) and thickness profiles (RaleighWX's model page), to get a better picture of implications of a slight westward shift. If an inland track were going to occur, I would expect to see at-least a couple ens members pick up on it, even 1. But the 12z GGEM and GFS members are all right along the coast, or for the majority, just offshore. As long as you are on the east side of the low by about 30 miles, you should be fine Veronica.

http://www.meteor.ia...m/gfs3_krwi.dat