ATL: EMILY - Remnants

[KWT]

Deepening over the Bahamas this run, I think the intial motion is probably a little too far east though...

Conditions look good through the Bahamas and into the W.Caribbean...so once it does lift out somewhat, the system does get into much better conditions...

[ConvergenceZone]

I actually think, based on the last few frames of the floater, that the LLC is starting to look better. A defined swirl with convection trying to build back in around it, while the blob to the SW starts to dissipate.

Emily has cried "wolf" too many times

[SouthDadeFish]

GFS has been very consistent, I'll give it that.

Favorable upper enviroment north of DR. If theres anything left watch out.

Been my thoughts for a while now. I'm growing more skeptical of anything being left though.

[ronjon]

12z GFS initialized too far east. Here is the 11 am model position. Plus the model has it moving almost N-NW from this point on.

12z GFS

[KWT]

i think she's lookin better and better in last hour
at least thru 1610utc

http://aviationweather.gov/adds/satelli ... &itype=vis

is anyone denyin thats a vigorous LLC

i mean yes wv...and infared look pathetic but the LLC is hanging tuff

I don't think the west winds are that strong, looking at a better resolution loop, i can see some but I'm betting recon only finds weak winds on thast southern side and it looks a bit less defined then a few hours ago, not as tightly wound.

[midnight8]

Looking at the models at Stormpulse.com. What about the Canadian that suggest this thing getting picked up NW and then turning back to the WNW or West off the west coast of Florida?

[SoupBone]

Vertical instability remains very low in the CAR and throughout the Atl Basin. Yes, this is a limited granularity measurement and admittedly observations drawn from this are weaker as a result. But this is a phenomena that dominated the 2010 Atlantic Basin season and I believe is influencing what we have seen thus far this season.

For my money - until I see instability improve - I believe the overall threat for well-organized systems remains less than it would be without the anomalously-low instabilities.

Could you explain this and dumb it down a bit for me? I'd like to understand it, but my limited scientific background is preventing me from fully grasping what this post means.

[TreasureIslandFLGal]

Doesn't a human set the starting coordinates and initial direction for the model to run off of? or is that automated (and continuously faulty)? -frustrating....since many of the models use teh GFS as their own starting points. So that means that once again, half of them will be way off and not even worthy to consider other than the synoptic setup they show AROUND Emily.

[KWT]

CMC looks like it nailed the track on its 00z run, so far it looks perfect based on its current motion.

[Portastorm]

I'm with you SoupBone ... I get how a lack of vertical instability can inhibit tropical cyclone development. I'd be curious to know what is the CAUSE of the lack of instability. Weak MJO signal? Nonstop shear? A lack of high pressure? Volatile upper-level winds from different directions? A combination of any of all of these?

[clfenwi]

On the ground, ready to go. ~ 1 hr flight time to the center once it takes off.

URNT15 KNHC 031640
AF306 0805A EMILY HDOB 02 20110803
163030 1742N 06449W 0110 ///// 0098 +279 +213 360000 000 /// /// 23
163100 1742N 06449W 0110 ///// 0098 +279 +213 360000 000 /// /// 23
163130 1742N 06449W 0110 ///// 0098 +282 +212 360000 000 /// /// 23
163200 1742N 06449W 0109 ///// 0097 +279 +212 360000 000 /// /// 23
163230 1742N 06449W 0110 ///// 0098 +280 +211 360000 000 /// /// 23
163300 1742N 06449W 0109 ///// 0097 +279 +211 360000 000 /// /// 23
163330 1742N 06449W 0109 ///// 0096 +280 +210 360000 000 /// /// 23
163400 1742N 06449W 0108 ///// 0096 +285 +210 360000 000 /// /// 23
163430 1742N 06449W 0108 ///// 0096 +286 +210 360000 000 /// /// 23
163500 1742N 06449W 0109 ///// 0097 +285 +210 360000 000 /// /// 23
163530 1742N 06449W 0108 ///// 0097 +286 +209 360000 000 /// /// 23
163600 1742N 06449W 0109 ///// 0096 +283 +209 360000 000 /// /// 23
163630 1742N 06449W 0109 ///// 0098 +283 +209 360000 000 /// /// 23
163700 1742N 06449W 0110 ///// 0098 +285 +208 360000 000 /// /// 23
163730 1742N 06449W 0110 ///// 0098 +284 +208 360000 000 /// /// 23
163800 1742N 06449W 0110 ///// 0098 +281 +208 360000 000 /// /// 23
163830 1742N 06449W 0110 ///// 0097 +279 +207 360000 000 /// /// 23
163900 1742N 06449W 0110 ///// 0099 +278 +206 360000 000 /// /// 23
163930 1742N 06449W 0112 ///// 0099 +274 +206 360000 000 /// /// 23
164000 1742N 06449W 0114 ///// 0099 +269 +205 106015 022 /// /// 23
$$

[Aric Dunn]

CMC looks like it nailed the track on its 00z run, so far it looks perfect based on its current motion.

look at the early track cmc... west turn end of run..

[TreasureIslandFLGal]

My amateur take on this: It takes instability in the atmosphere to get thunderstorms to crank. Since the Caribbean has had pretty consistent (and dull) stability between multiple heights, including their moisture content and heat energy, the instability of the air is low. Higher levels of instability would be conducive for development.

[TreasureIslandFLGal]

includes all of the above... moisture content, heat, consistent directional winds (layers not going in different wind directions).

i.e. supercells that produce tornadoes require different wind directions at different heights to produce the cyclonic spin required to produce a tornado. If all height going the same direction, no issues.

[xironman]

I actually think, based on the last few frames of the floater, that the LLC is starting to look better. A defined swirl with convection trying to build back in around it, while the blob to the SW starts to dissipate.

Emily has cried "wolf" too many times

You remember what happen the third time wolf was cried right? This thing is hilarious, starting to pop convection near the LLC. I am giving up on guessing what it is going to do and just going along for the ride.

[Shuriken]

Decoupling in the east-Carr means tracking left of model consensus.

I.e., Emily misses the Greater Antilles to menace the Gulf later on instead of getting shredded by Hispaniola and then passing harmlessly up the east coast..

[ronjon]

High res VIS SAT showing the LLC crossing over 70W now. Movement due west and at a fairly good clip. It will pass the southern most point of Hispaniola within 3-4 hrs at this rate. If it doesn't change direction soon, it will miss the big island.

http://rammb.cira.colostate.edu/ramsdis/online/loop_640.asp?product=tropical_ge_1km_center_relative_vis_floater

[underthwx]

THE LOW-LEVEL CENTER HAS CONTINUED TO MOVE TOWARD THE WEST OR 280
DEGREES AT 12 KNOTS. ASSUMING EMILY CAN MAINTAIN A VERTICALLY DEEP
CIRCULATION...THE CYCLONE SHOULD SOON TURN MORE TO THE NORTHWEST
AND EVENTUALLY TOWARD THE NORTH AROUND THE PERIPHERY OF THE
SUBTROPICAL RIDGE. ALTHOUGH THERE HAS NOT BEEN A SIGNIFICANT CHANGE
IN THE STEERING PATTERN SOME OF THE GUIDANCE HAS SHIFTED SLIGHTLY
WESTWARD...AND SO HAS THE OFFICIAL FORECAST. THE GFS REMAINS ALONG
THE EASTERN EDGE OF THE GUIDANCE ENVELOPE.

11:00NHC...........my question is........are the models having difficulty responding due to uncertainty of what the strength of the system will be down the road?

[mitchell]

The Labor Day Hurricane in 1935 went from just becoming a hurricane to a Cat 5 in approximately 24 hours...but obviously it had ideal conditions to work with.

http://en.wikipedia.org/wiki/1935_Labor_Day_hurricane

I often wonder how reliable those type of data are from 80 years ago.

[TreasureIslandFLGal]

Aric, the CMC looks like it could be setting up a fun little loop da loop or stalled out scenario if the ridge then peters out and it has to await another approaching trough/weakness to give it steering back to the north and east. That TX dath ridge looks like it is in no hurry to break.