ATL: RICHARD - Remnant Low - Discussion

[Sanibel]

Black IR burst and better organization. I can see why they TD'd it.

[Ntxw]

Very impressive! Well on it's way to a TS imo.

[Sanibel]

The hugely obvious dry air on WV speaks for itself and should limit intensity.

[StormingB81]

Well that would be good...

[Extratropical94]

The models see this different.
All going for (at least) cat. 1 as of 06z.

Quite interested whether the NHC pushes the intensity forecast or not with the 5am update.

[Extratropical94]

5am Discussion


000
WTNT44 KNHC 210842
TCDAT4
TROPICAL DEPRESSION NINETEEN DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL192010
500 AM EDT THU OCT 21 2010

THE THUNDERSTORM ACTIVITY HAS INCREASED DURING THE PAST SEVERAL
HOURS AND THERE HAS BEEN SOME INCREASE IN ORGANIZATION. ALTHOUGH
THE SHEAR SEEMS TO BE RELAXING AS INDICATED BY MOTION OF THE HIGH
CLOUDS...THE CENTER IS STILL LOCATED ON THE WESTERN PORTION OF A
CYCLONICALLY CURVED CONVECTIVE BAND. SATELLITE INTENSITY ESTIMATES
FROM BOTH TAFB AND SAB ARE 2.5 ON THE DVORAK SCALE...INDICATING
THAT THE DEPRESSION COULD BE A TROPICAL STORM. HOWEVER...AN AIR
FORCE PLANE WILL BE IN THE AREA IN A FEW HOURS...AND I WOULD RATHER
WAIT FOR THE RECONNAISSANCE DATA TO UPGRADE THE SYSTEM TO A
TROPICAL STORM. HAVING SAID THAT...MOST OF THE GLOBAL MODELS ARE
SHOWING THE DEVELOPMENT OF AN UPPER-LEVEL ANTICYCLONE NEAR OR OVER
THE DEPRESSION IN A DAY OR SO...AND A TRACK A LITTLE BIT MORE
DISTANT FROM THE HIGH TERRAIN OF CENTRAL AMERICA. THESE CONDITIONS
AND THE PREVAILING WARM OCEAN WOULD BE FAVORABLE FOR
INTENSIFICATION. THE OFFICIAL FORECAST CALLS FOR A LITTLE MORE
STRENGTHENING THAN INDICATED IN THE PREVIOUS ADVISORY BUT NOT AS
AGGRESSIVE AS THE GFDL AND THE HWRF. THE DEPRESSION IS FORECAST TO
BECOME A HURRICANE IN THE NORTHWESTERN CARIBBEAN AS INDICATED BY
THE INTENSITY MODEL CONSENSUS.


THE DEPRESSION HAS BEEN MOVING SLOWLY TOWARD THE SOUTHEAST OR 135
DEGREES AT 3 KNOTS...EMBEDDED IN VERY LIGHT STEERING CURRENTS.
LITTLE MOTION IS ANTICIPATED DURING THE NEXT DAY OR SO.
THEREAFTER...ALL GLOBAL MODELS LIFT OUT THE CURRENT TROUGH OVER THE
WESTERN ATLANTIC AND REPLACE IT WITH A SUBTROPICAL RIDGE. THIS NEW
STEERING PATTERN WOULD FORCE THE CYCLONE ON A WEST TO WEST-NORTHWEST
TRACK ACROSS THE NORTHWESTERN CARIBBEAN SEA AND THE YUCATAN
PENINSULA. THE OFFICIAL TRACK FORECAST HAS SHIFTED A LITTLE BIT TO
THE NORTH...AND IS HEAVILY BASED ON THE GFS...THE UK MODELS AND
CONTINUITY. I HAVE LESS CONFIDENCE IN THE FORECAST BEYOND 72 HOURS
BECAUSE THE GFDL...THE HWRF AND THE ECMWF TURN THE CYCLONE TOWARD
THE NORTH OVER THE YUCATAN CHANNEL AND THE SOUTHEASTERN GULF OF
MEXICO. I WOULD NOT BE SURPRISED IF THE TRACK HAS TO BE ADJUSTED
NORTHWARD LATER ON.


FORECAST POSITIONS AND MAX WINDS

INITIAL 21/0900Z 17.0N 80.7W 30 KT
12HR VT 21/1800Z 16.8N 80.7W 40 KT
24HR VT 22/0600Z 16.5N 81.0W 45 KT
36HR VT 22/1800Z 16.5N 81.5W 55 KT
48HR VT 23/0600Z 16.5N 82.0W 65 KT
72HR VT 24/0600Z 17.5N 84.5W 65 KT
96HR VT 25/0600Z 19.0N 88.0W 40 KT...INLAND
120HR VT 26/0600Z 21.0N 90.0W 30 KT...INLAND

$$
FORECASTER AVILA

[weatherwindow]

track may shift right......500am nhc discussion...per avila.."the official track has shifted a bit to the north....i have less confidence in the forecast beyond 72 hours because the gfdl, the hwrf and the ecmwf turn the cyclone toward the north over the yucatan channel and the southeastern gom. i would not be surprised if the track had to be adjusted northward later on.".....perhaps a threat to western cuba and the straits?

[DESTRUCTION5]

THE OFFICIAL TRACK FORECAST HAS SHIFTED A LITTLE BIT TO
THE NORTH...AND IS HEAVILY BASED ON THE GFS...THE UK MODELS AND
CONTINUITY. I HAVE LESS CONFIDENCE IN THE FORECAST BEYOND 72 HOURS
BECAUSE THE GFDL...THE HWRF AND THE ECMWF TURN THE CYCLONE TOWARD
THE NORTH OVER THE YUCATAN CHANNEL AND THE SOUTHEASTERN GULF OF
MEXICO. I WOULD NOT BE SURPRISED IF THE TRACK HAS TO BE ADJUSTED
NORTHWARD LATER ON.

Climo taking over...

[GCANE]

Even though the air to the west looks dry on WV, it is in fact unstable.

http://www.goes.noaa.gov/HURRLOOPS/huwvloop.html

http://www.ssd.noaa.gov/goes/flt/t1/loop-ft.html

Lifted Index (LI) is about -4 near the convection and then drops to about 0 at the coast.

Latest sounding at 18N 83W shows LI = -2, CAPE = 1001.

As expected, over the Yucatan landmass LI becomes positive.

As usual, air over the landmass should destabilize in the afternoon due to solar heating.

That could provide an added infeed and TD19 could ramp up then.

WV shows moisture in the 600 to 300mb level not in the boundary layer.

MIMIC-TPW is better for showing moisture in the boundary layer.

http://cimss.ssec.wisc.edu/tropic/real- ... t72hrs.gif

Doesn't look bad at all with CCW convergence and darkening pixels.

TC infeeds are mostly from the boundary layer.

[GCANE]

Looks like the anti-cyclone is now very close to being over the convection and LLC.

North and west UL outflow appears to be picking up quickly and is venting nicely due to the poleward outflow channel in place.

http://www.ssd.noaa.gov/goes/flt/t1/loop-rgb.html

Also looks like an equatorward outflow channel is developing as well.

Today should be a good day for "soon to be" Richard.

[wxman57]

NHC track looks too slow, too weak, and too far to the west. It could just hit the northern Yucatan as a major hurricane next Monday and remain a hurricane in the southern Gulf (vs. a TD). But with high pressure building over south Florida, it may have nowhere to go but N-NNE toward the FL Panhandle. I don't see it going to south FL, though.

[cycloneye]

57,there will be a strong Cold Front comming by mid next week right?

[dwsqos2]

The center is still pretty broad based on the latest recon data.

[KWT]

Thats exactly what I think Wxman57, the limiting factor is indeed the dry air to its west but in this situation a developing storm tends to be able to over ride that anyway.

I said in the model page my biggest threat zone right now would be the Yucatan...the good news is the panhandle hit would probably mean a shedload of shear that far north, so maybe the end result would end up being Ida from last year rather then anything stronger

[wxman57]

57,there will be a strong Cold Front coming by mid next week right?

The strong front isn't likely to move off the Texas coast until next Thursday. Richard could enter the south-central Gulf Monday during the day on Monday. High pressure to the east could steer it toward a certain S2K member who hates Ivan in the Fl Panhandle. Good news is the models forecast about 50kt SW winds aloft across the central Gulf, so it could do an "Ida" as it tracks toward the coast. But I think it could be a strong but sheared TS at landfall.

[xironman]

About the time the Euro gets it the panhandle, the shear is nothing like it is right now.

[gatorcane]

THE OFFICIAL TRACK FORECAST HAS SHIFTED A LITTLE BIT TO
THE NORTH...AND IS HEAVILY BASED ON THE GFS...THE UK MODELS AND
CONTINUITY. I HAVE LESS CONFIDENCE IN THE FORECAST BEYOND 72 HOURS
BECAUSE THE GFDL...THE HWRF AND THE ECMWF TURN THE CYCLONE TOWARD
THE NORTH OVER THE YUCATAN CHANNEL AND THE SOUTHEASTERN GULF OF
MEXICO. I WOULD NOT BE SURPRISED IF THE TRACK HAS TO BE ADJUSTED
NORTHWARD LATER ON.

Climo taking over...

Indeed. That is why I was posting last night how i was in disbelief about why some thought it was definitely head in to the yucatan.

I see the ridge collapsing and this system may do what the gfdl and hwrf suggest

[HURRICANELONNY]

I think if it gets into the Gulf next week it will be a sheared mess. Lots more shear in the Gulf this time of year then it was for Wilma. Heck Wilma sat on the Yucatan waiting for the trough for days. I say a tropical storm hitting central florida sometime next week. That's my guess.

[gatorcane]

NHC track looks too slow, too weak, and too far to the west. It could just hit the northern Yucatan as a major hurricane next Monday and remain a hurricane in the southern Gulf (vs. a TD). But with high pressure building over south Florida, it may have nowhere to go but N-NNE toward the FL Panhandle. I don't see it going to south FL, though.

Really? Both hurricane models suggest sw Florida. Climo argues strongly for a south Florida hit. I'm not sure either but it's possible peninsula Florida could be an eventual target looking at the models.

[KWT]

I wouldn't be surprised if it does still end up hitting the YUcatan Gatorcane but its far from certain at this stage as you rightly say, I personally suspect it will graze the Yucatan then move NNE and probably be a hurricane as well...no sure about major just yet though...