0Z model discussion

[PhineasC]

Guys, don't get too excited. GFS ensembles are well east of the operational and the GGEM is still well OTS. There isn't enough time to save NYC south barring a miracle. All we are getting is a slightly closer miss.

[mattinpa]

Guys, don't get too excited. GFS ensembles are well east of the operational and the GGEM is still well OTS. There isn't enough time to save NYC south barring a miracle. All we are getting is a slightly closer miss.

But remember when they were west of the OP, the OP shifted east. Every global went west so far, so that is good.

[TowsonWeather]

I was thinking this but didn't want to get crucified by saying it.

This radar loop is just awesome: http://www4.ncsu.edu/~nwsfo/storage/cases/20000125/

[Amped]

Like 1/25/2000 in terms of high sensitivity to latent heat.. A little extra convection in the gulf that drops pressures a few mb could go a long way.

[baroclinic_instability]

I am pretty sure the great Euro runs had the low forming off the Carolina coast. I don't think that is the issue.

The great Euro runs had a GOM influence and needed the low level diabatic heat release in the low levels to enhance both the warm air advection, but also to decrease static stability which aids a ton in development of a baroclinic system and is common in rapid cyclogenesis. Bombing off the Gulf Stream is obviously a common occurence, but the configuration of this system needed both the GOM and Gulf Stream.

[TowsonWeather]

Like 1/25/2000 in terms of high sensitivity to latent heat.. A little extra convection in the gulf that drops pressures a few mb could go a long way.

http://www4.ncsu.edu/~nwsfo/storage/cases/20000125/

"As the deepening upper-level wave drew cold air southward, precipitation began falling into the relatively dry air airmass over the state, and surface temperatures fell to below freezing across much of the area. The upper-level support, coupled with a pre-existing baroclinic zone draped across the southeast, allowed the surface low to rapidly strengthen off the South Carolina coast. As the area of new convection moved across the Southeast, it rapidly merged with the developing low pressure, creating an "instant occlusion" of the storm, which leads to rapid cyclogenesis. Heavy snow began to fall just after midnight in the Raleigh-Durham area on the 25th (see surface observations below). The low pressure system would eventually deepen to around 986mb and move up the Atlantic seaboard, spreading snow across much of the Mid-Atlantic and New England by 06Z on the 26th."

[SnowGoose69]

Guys, don't get too excited. GFS ensembles are well east of the operational and the GGEM is still well OTS. There isn't enough time to save NYC south barring a miracle. All we are getting is a slightly closer miss.

Thats what I'm feeling as well for now.

[jlewis1111]

Synoptic Overview

As the January 23 storm system and upper-level jet began to lift northeast away from North Carolina, a second short-wave trough was digging southeastward into the Deep South. At 00Z on the 24th, a large area of precipitation associated with the departing storm stretched from the North Carolina coast through northern Florida. At around 06Z, an area of convection developed along the Gulf Coast over Louisiana and Southern Mississippi. By 12Z, the upper-level short-wave had begun to amplify and become negatively tilted, and a low pressure system formed over northern Florida.

As the deepening upper-level wave drew cold air southward, precipitation began falling into the relatively dry air airmass over the state, and surface temperatures fell to below freezing across much of the area. The upper-level support, coupled with a pre-existing baroclinic zone draped across the southeast, allowed the surface low to rapidly strengthen off the South Carolina coast. As the area of new convection moved across the Southeast, it rapidly merged with the developing low pressure, creating an "instant occlusion" of the storm, which leads to rapid cyclogenesis. Heavy snow began to fall just after midnight in the Raleigh-Durham area on the 25th (see surface observations below). The low pressure system would eventually deepen to around 986mb and move up the Atlantic seaboard, spreading snow across much of the Mid-Atlantic and New England by 06Z on the 26th.

[forkyfork]

21z sref storm tracks

[IsentropicLift]

Guys, don't get too excited. GFS ensembles are well east of the operational and the GGEM is still well OTS. There isn't enough time to save NYC south barring a miracle. All we are getting is a slightly closer miss.

It's one thing to be conservative but your way to quick to pass judgement and make calls. Last time I checked your no red tagger. We all saw how the 18z GFS ensemble mean shifted east yet the op continued to trend west. Just about every model thus far has improved in its 00z package in some way shape or form.

[WhiteoutWX]

21z sref storm tracks

Do you have 15z for comparison?

[ohleary]

THERE could be an ASPECT TO JAN 2000 in this

Only as far as a system shifting west with successive model runs inside 48 hours. The synoptic setup was completely different.

[forkyfork]

Do you have 15z for comparison?

[Guest someguy]

The great Euro runs had a GOM influence and needed the low level diabatic heat release in the low levels to enhance both the warm air advection, but also to decrease static stability which aids a ton in development of a baroclinic system and is common in rapid cyclogenesis. Bombing off the Gulf Stream is obviously a common occurence, but the configuration of this system needed both the GOM and Gulf Stream.

PRECISELY

perfectly stated

[PhineasC]

It's one thing to be conservative but your way to quick to pass judgement and make calls. Last time I checked your no red tagger. We all saw how the 18z GFS ensemble mean shifted east yet the op continued to trend west. Just about every model thus far has improved in its 00z package in some way shape or form.

They have been "improving" for days according to some folks and yet the track has remained off-shore for the most part. Once the Euro folded, this threat was mostly dead south of NYC.

[baroclinic_instability]

It's one thing to be conservative but your way to quick to pass judgement and make calls. Last time I checked your no red tagger. We all saw how the 18z GFS ensemble mean shifted east yet the op continued to trend west. Just about every model thus far has improved in its 00z package in some way shape or form.

I don't agree with Phineas all the time, but this time he is right. Mid-Atlantic would need some sort of unseen miracle to hook this storm into the coast. It has become clear the southern PV anomaly is very weak and will not aid in explosive development early enough in the cyclogenesis process. At best, this storm begins tanking off the Gulf Stream around SC. Given the orientation of the system, a hook into the Mid-Atlantic like the ECM had earlier is basically impossible.

[ohleary]

It's one thing to be conservative but your way to quick to pass judgement and make calls. Last time I checked your no red tagger. We all saw how the 18z GFS ensemble mean shifted east yet the op continued to trend west. Just about every model thus far has improved in its 00z package in some way shape or form.

Exactly the reason to be skeptical...

[PhineasC]

21z sref storm tracks

Looks like two members jumped west from the previous run, causing the mean to come west a bit as well.

[Bob Chill]

The Jan 2000 storm was the best total surprise in my recent memory. I went to bed around midnight looking at the radar thinking that the 11pm TV Mets are way wrong but "what the heck do I know?" crossed my mind and went to bed. Drove to my office in downtown DC at 5am thinking WTF? Watched the wind whipped snow dump until noon.

Regardless of the models, how many people on here will be watching radar loops Xmas night and Sunday morning? Weenie wishcasting and weenie halucinations at their finest.

[Clinch Leatherwood]

I don't agree with Phineas all the time, but this time he is right. Mid-Atlantic would need some sort of unseen miracle to hook this storm into the coast. It has become clear the southern PV anomaly is very weak and will not aid in explosive development early enough in the cyclogenesis process. At best, this storm begins tanking off the Gulf Stream around SC. Given the orientation of the system, a hook into the Mid-Atlantic like the ECM had earlier is basically impossible.

And I'll agree as well. There's always an element of chaos that could change things, but we've been hearing it's better for 2-3 days and it's still questionable all the way up in NE.

Subjectively looking at the GGEM/NOGaps/UK/GEFS/NAM/RGEM all are still largely a miss. It's the OP GFS, and whatever the EC shows.

[IsentropicLift]

They have been "improving" for days according to some folks and yet the track has remained off-shore for the most part. Once the Euro folded, this threat was mostly dead south of NYC.

incorrect....for the most part, the models held serve for several days just as the Euro held its outlier solution. The GFS trended way OTS then came back a bit yesterday. It was not unitl today's 18z run that a glimmer of hope first showed up. I have a feeling that the euro which has been holding back the energy longer in the SW all along will have it phase with that tremendous amount of energy diving down from the midwest just in time. Not saying this is definitly going to happen but you just can't ignore the 00z trends and say you have made a proper analyization.

[SnowGoose69]

The Jan 2000 storm was the best total surprise in my recent memory. I went to bed around midnight looking at the radar thinking that the 11pm TV Mets are way wrong but "what the heck do I know?" crossed my mind and went to bed. Drove to my office in downtown DC at 5am thinking WTF? Watched the wind whipped snow dump until noon.

Regardless of the models, how many people on here will be watching radar loops Xmas night and Sunday morning? Weenie wishcasting and weenie halucinations at their finest.

That event was blown largely due to some Upper air sonde from the SE US being rejected by the models, maybe Atlanta.....the only similarity I see in this event could be that the models may be missing the magnitude of negative tilt the 500 trough will take on once the low forms in the SE, if that is being underestimated this system could ultimately go due northward or NNE enough to impact the NE and MA.

[Guest someguy]

Only as far as a system shifting west with successive model runs inside 48 hours. The synoptic setup was completely different.

yes of course

Let me clairify

what I meant was ... that in the jan 25 2000 event ..it seems to me that the model mis fire that occurred in the medium and short range wasdue to the fact that the Upstream s/w was

viewed as a "kicker" for the lead s/w over the se states

instead it dropped south it caused the wavelenght to alter and the downstream ridge to increase ... so that the lead s/w over the se states could not fly off the coast and out to sea

In this case I am wondering if there is enough upstream energy in the northern branch plunging south to cause the main s/w to sharp enough Just enough to pull it back west a tad

[Guest someguy]

That event was blown largely due to some Upper air sonde from the SE US being rejected by the models, maybe Atlanta.....the only similarity I see in this event could be that the models may be missing the magnitude of negative tilt the 500 trough will take on once the low forms in the SE, if that is being underestimated this system could ultimately go due northward or NNE enough to impact the NE and MA.

yes that is EXACTLY what I meant

[Dino]

any possibility in the track of the low pressure staying the same, but the precip shield expanding westward?

[Dr No]

any possibility in the track of the low pressure staying the same, but the precip shield expanding westward?

your name says it all.... further south the better.

[weatherweather]

DT, this northstream kicker you mention is that what was causing the trough to widen on yesterdays gfs runs?

[SnowGoose69]

This event resembles 2/89, 3/09 and 1/25/00...overall all 3 systems tracked more north than northeast and needed a major negative tilt at 500 because the ridge was displaced too far east out in the west or was progressing eastward at the time....1/25/00 and 3/09 got it...this one might but I doubt it.

[gymengineer]

The Jan 2000 storm was the best total surprise in my recent memory. I went to bed around midnight looking at the radar thinking that the 11pm TV Mets are way wrong but "what the heck do I know?" crossed my mind and went to bed. Drove to my office in downtown DC at 5am thinking WTF? Watched the wind whipped snow dump until noon.

Regardless of the models, how many people on here will be watching radar loops Xmas night and Sunday morning? Weenie wishcasting and weenie halucinations at their finest.

This could not have been the case--- the Winter Storm Warning came out before 10 pm. Earlier, at 5 pm, the TV Mets were pretty much unanimous in saying that something was way off with the radar compared to the modeling in South Carolina. The NWS issued the rapid-response WSW at 9:48 pm and the 11 pm newscasts led with that as the top story.

[Bob Chill]

That event was blown largely due to some Upper air sonde from the SE US being rejected by the models, maybe Atlanta.....the only similarity I see in this event could be that the models may be missing the magnitude of negative tilt the 500 trough will take on once the low forms in the SE, if that is being underestimated this system could ultimately go due northward or NNE enough to impact the NE and MA.

I totally agree and undertand that this setup isn't capable of what happened in 2000 but that event will always keep people on their toes when N & S stream energy has the potential to phase (or the phase is modeled incorrectly).

Although I don't think the threat is real for the MA at this point, I'm sure mets will be paying close attention to the real time interaction of the 2 streams just in case the evolution raises a red flag compared to the modeled solutions.