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East Coast Threat/Sandy Part III


free_man

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can someone explain why a stronger storm would go out to sea. Shouldnt this also enhance downstream ridging?

Going out to see isn't really correct. Downstream ridging is enhanced, but sometimes storms with very deep convection are directed by winds not just in the mid levels..but also upper levels. This sometimes causes storms to be affected by slight nuances in the flow at upper levels.

However, latent heat pumps up downstream ridging. That outflow channel is a diabatic heat pump.

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can someone explain why a stronger storm would go out to sea. Shouldnt this also enhance downstream ridging?

can anyone explain what the box disco was saying about the longer this maintains as a warm core tropical system the more resistant to phasing it will be in crossing 5h heights and 1000-500mb thicknesses.

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Going out to see isn't really correct. Downstream ridging is enhanced, but sometimes storms with very deep convection are directed by winds not just in the mid levels..but also upper levels. This sometimes causes storms to be affected by slight nuances in the flow at upper levels.

However, latent heat pumps up downstream ridging. That outflow channel is a diabatic heat pump.

I think in this case stronger outflow and a stronger/larger storm may prevent it from losing much longitude. The weakness in the ridge near Bermuda is minimal... the GFS tries to exploit it... but a stronger storm may pump up the ridging enough.

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can anyone explain what the box disco was saying about the longer this maintains as a warm core tropical system the more resistant to phasing it will be in crossing 5h heights and 1000-500mb thicknesses.

If you read the entire thing, it tells you why.

The Caine vort becomes more dominant and resistant to the weaker vort entrained in the trough. Hence, a later phase, a longer phase so to speak..

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can anyone explain this (great disco anyway)

WITH GREATER CONFIDENCE...A MAJORITY OF ENSEMBLE AND OPERATIONAL

MODEL SOLNS FORECAST HURRICANE SANDY LIFTING NORTHWARD...BECOMING

POST-TROPICAL /REMAINING WARM-CORED/ AS IT LOOPS WEST TOWARDS THE

RIGHT-REAR QUADRANT OF THE AFOREMENTIONED UPPER LVL JET /SOMEWHERE

IN PROXIMITY TO THE ERN GREAT LAKES REGION/ PARENT WITH THE

NEGATIVELY TILTING TROUGH ACROSS THE GRT LAKES RGN.

BUT AM HESITANT TO BUY INTO THE MAJORITY OF SOLNS...THE STORM IS

TAKING ON A HISTORICAL PRECEDENT COMPARED TO THE CLIMATOLOGY OF

OTHER POST-TROPICAL SYSTEMS DURING THE AUTUMN MONTHS. WITH REGARDS

TO THE LITERARY DISCUSSION YESTERDAY...THE POST-TROPICAL TRACK OF

SANDY IS SLIGHTLY ANOMALOUS TO BENCHMARK TRACKS OF THE GREAT GALE OF

1878 AND HURRICANE HAZEL IN 1954 /THOUGH HAZEL DID EXHIBIT A SLIGHT

WESTWARD LEAN IT IS TRACK/.

IN ADDITION...THROUGH PERSONAL COMMUNICATION...MODEL SOLNS HAVE BEEN

KNOWN TO PREMATURELY PHASE SYSTEMS BEYOND 120 HRS /ESPECIALLY A

TROPICAL SYSTEM PHASING INTO A TROUGH/. SO LONG AS HURRICANE SANDY

MAINTAINS...THE LONGER IT MAY RESIST CROSS H5 HEIGHTS AND 1000-500

THICKNESSES...RESULTING IN A GREATER PROBABILITY OF A TRACK TO THE

RIGHT /ESPECIALLY IF IT TRACKS QUICKER AVOIDING THE TROUGH INTO THE

GREAT LAKES REGION/. BUT AS SEEN IN MODEL SOLNS...SANDY SLOWS WITH A

BLOCKING PATTERN TO THE EAST...AND SHOULD IT TRANSITION POST-

TROPICAL...SANDY WOULD BE ALLOWED TO PHASE ACROSS H5 HEIGHTS WITH A

SUBSEQUENT LEFT HOOK.

ADDITIONAL COMMUNICATION HAS BROUGHT UP POINTS CONCERNING OVER-

ZEALOUS CYCLONE DEEPENING BY MODEL SOLNS...AS WELL AS HANDLING STORM

MERGERS POORLY. SHOULD A MERGER OCCUR...THE MORE DOMINANT WAVE

SHOULD USURP THE WEAKER WAVE AND PREVAIL.

After reading this post (I guess from an AFD - KBOX' ?) and looking at the ongoing intensification of Sandy and then looking at the forecast post tropical forecast pressures for the storm I got to thinking about my days as a marine meteorologist and ship router. My mentor said that a good rule to follow for the strength of a XTC after TC "instransification" is that as an XT low the central pressure is rarely lower than the lowest pressure when that cyclone was tropical.

===

now cpick: The answer for first part of the bolded AFD is basically that surface lows as they intensify especially those associated with a cold trough or cut off low aloft tend to move towards colder air (cut across thickness lines). Warm core systems tend not to do this.

The latter part of the bolded post simply put survival of the fittest or in this case most intense low will "abosrb" the weaker low.

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After reading this post (I guess from an AFD - KBOX' ?) and looking at the ongoing intensification of Sandy and then looking at the forecast post tropical forecast pressures for the storm I got to thinking about my days as a marine meteorologist and ship router. My mentor said that a good rule to follow for the strength of a XTC after TC "instransification" is that as an XT low the central pressure is rarely lower than the lowest pressure when that cyclone was tropical.

===

now cpick: The answer for first part of the bolded AFD is basically that surface lows as they intensify especially those associated with a cold trough or cut off low aloft tend to move towards colder air (cut across thickness lines). Warm core systems tend not to do this.

The latter part of the bolded post simply put survival of the fittest or in this case most intense low will "abosrb" the weaker low.

Which would mean a greater chance of a phase since the weaker low is absorb rather than a curve out to sea?

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I think in this case stronger outflow and a stronger/larger storm may prevent it from losing much longitude. The weakness in the ridge near Bermuda is minimal... the GFS tries to exploit it... but a stronger storm may pump up the ridging enough.

If it continues, that's going to hurt any weakness to the northeast. That thing is off to the races.

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I think in this case stronger outflow and a stronger/larger storm may prevent it from losing much longitude. The weakness in the ridge near Bermuda is minimal... the GFS tries to exploit it... but a stronger storm may pump up the ridging enough.

TC's tend to move along/towards warm tongue aloft (usually noted by 700-500 millibar thickness) are good for determining short 24 hour motion.

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Which would mean a greater chance of a phase since the weaker low is absorb rather than a curve out to sea?

Yes but this would assume Sandy IS the weaker low and a stronger coastal low forms associated with the C/O low. Now Sandy could remain strong and still get captured but not until "later" and or further north.

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Yes but this would assume Sandy IS the weaker low and a stronger coastal low forms associated with the C/O low. Now Sandy could remain strong and still get captured but not until "later" and or further north.

what i took away by reading it was basically that the 12z ecmwf OP was not really believable by box , bc a tropical sandy of that strength (being the dominant low also) would be more hesitant to phase and it is generally less likely of a mid atlantic left hook. unless sandy becomes a real mess by the carolina's and a LP from the Ohio valley SW is bombing?

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With the phase... no phase million dollar question i.e keeping as a true tropical system. One would think the forward speed and track would be influenced possibly taking that left hook dependent on the axis and strength of the trof?

To some degree I would say yes but also the TC's size and strength come to bear. Its hard for a "massive" system to change its momentum rather abruptly. Think of a tractor trailer rig and a car on a road both going at the same speed. The car can stop sooner the truck can't.

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what i took away by reading it was basically that the 12z ecmwf OP was not really believable by box , bc a tropical sandy of that strength (being the dominant low also) would be more hesitant to phase and it is generally less likely of a mid atlantic left hook. unless sandy becomes a real mess by the carolina's and a LP from the Ohio valley SW is bombing?

I can't really say what they were referring too; perhaps in a general way they were referring to some of the seemingly extreme pressure forecasts from the many model sources.

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All I want to see tonight is for the NAM to continue having a Euro-like look to it and for the Euro to continue being consistent...that to me will say alot...I wouldn't even really care what the GFS does or shows.

21z SREFs at 87 hrs SLP position are spread out like a zoo

http://www.emc.ncep.noaa.gov/mmb/SREF/FCST/COM_US/ens.2012102421/surface_prs_87.gif

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21z SREFs at 87 hrs SLP position are spread out like a zoo

http://www.emc.ncep....face_prs_87.gif

I really wouldn't expect anything less too be honest with regards to track right now. I know the track is important down the road, however, without sufficient troughing or blocking we can forget a phase in time for this to happen...before I worry about track and such I want to at least see consistency with the evolution of the trough and how the blocking is handled.

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