ATL: HARVEY - Post-Tropical - Discussion

[colbroe]

91l is not listed on the NRL Monterey Marine Meteorology Division web site any more , so i am assuming the it no longer an area of interest.

[hd44]

91l is not listed on the NRL Monterey Marine Meteorology Division web site any more , so i am assuming the it no longer an area of interest.

It is. Percentages up to 40/50

[Alyono]

I think I spot an error in NHCs thinking of 40/50 for genesis probs

They are going with the old rule that the East Caribbean is unfavorable. That is a wrong line of thinking here and is misinterpreting the dynamics and thermodynamics of the current atmosphere.

Often, the EC is unfavorable as SAL surges accelerate due to the enhanced trades. In this case, there is not going to be a surge overtaking the system as it will be interacting with the 2 disturbances behind. There is SAL ahead from a previous outbreak. However, that is in the form of dry air only. There is not likely to be the strong low level easterly wind jet. Thus, the dry air should be moderating in the EC, which will cause conditions to be more favorable than they currently are. Thus, I would not rule out significant intensification, especially when this reaches the NW Caribbean where the dry air will have moderated further (or the storm will have escaped it)

[cycloneye]

2 PM TWO up to 40%/50%

A low pressure system located about 800 miles east of the Lesser
Antilles has become a little better defined since yesterday, but
most of the associated shower and thunderstorm activity is
displaced to the west of the center of circulation. Upper-level
winds are forecast to become more conducive for development during
the next day or so while the low moves westward at 15 to 20 mph
across the tropical Atlantic Ocean, crossing into the Caribbean Sea
on Friday. An Air Force Reserve reconnaissance aircraft is
scheduled to investigate this system on Thursday, if necessary, and
interests in the Lesser Antilles should monitor the progress of the
disturbance.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...medium...50 percent.

[cycloneye]

18z Best Track:

AL, 91, 2017081618, , BEST, 0, 136N, 490W, 25, 1009, LO

[Gustywind]

000
AXNT20 KNHC 161807
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
207 PM EDT Wed Aug 16 2017

A 1010 mb low is centered over the tropical Atlantic near 14N47W,
moving W at 15-20 kt. This wave in a very moist area based on
SSMI TPW imagery and is also reflected at 700 mb. Scattered
moderate to isolated strong convection is W of the low center from
12N-16N between 49W-53W. The low shows signs of gradual
development. There is a medium chance of tropical cyclone
formation within the next 48 hours.

[Nimbus]

91L has a smaller but better defined low level circulation with a tight pressure gradient.
Could be classified a TD at any time but I gather they are taking into consideration a hostile environment in the Caribbean?

[floridasun78]

so look this could beat 92l to next name system?

[gatorcane]

I am guessing this one becomes Harvey and the 92l becomes Irma. Irma, that name sounds creepy!

[Emmett_Brown]

Glancing at the GFS shear forecast, the shear will lessen as 91L approaches the Caribbean, and once an anticyclone gets established, the shear is only light to moderate. Should be a good environment in the Caribbean. If it gets wound up enough, I can see the outflow of 91L future Harvey suppressing 92L, keeping it in check. I guess the converse could be true as well, since they are pretty close to each other. Whichever one takes off first may be the one that ultimately survives.

[Nimbus]

The outflow from 91L is currently minuscule and probably well modeled as far as pumping up an anticyclone. So if there was intensification before the Caribbean then the models are probably trash since they are expecting a wave.

just reiterating..

[Sanibel]

The islands might serve to separate 91 from 92. That might give it slightly better southerly inflow.


Tiny center burst right now (life)...

[srainhoutx]

Latest 1km Zoomed Visible Imagery suggests showers and thunderstorm activity is slowly increasing as it nears 50W. It's just a matter of time before this disturbance is upgraded to a TD or TS.

[davidiowx]

I am guessing this one becomes Harvey and the 92l becomes Irma. Irma, that name sounds creepy!

I am not a fan of the "I" named storms

[cycloneye]

@BigJoeBastardi
Expect 91L to be elevated to high prob and be a storm by islands Friday. watches/warnings should go up tom.

 https://twitter.com/BigJoeBastardi/status/897932941120196609

[Thetxhurricanemaster]

@BigJoeBastardi
Expect 91L to be elevated to high prob and be a storm by islands Friday. watches/warnings should go up tom.

 https://twitter.com/BigJoeBastardi/status/897932941120196609

Here is really confident it still needs to sustain convection overnight let's see what the NHC thinks later

[Thetxhurricanemaster]

Latest 1km Zoomed Visible Imagery suggests showers and thunderstorm activity is slowly increasing as it nears 50W. It's just a matter of time before this disturbance is upgraded to a TD or TS.

I think it is definitely organizing gradually and by tomorrow night it will be at depression status

[tropicwatch]

Just had a WindSat pass but they missed. Hopefully we will have a good ASCAT pass tonight.

[Thetxhurricanemaster]

Just had a WindSat pass but they missed. Hopefully we will have a good ASCAT pass tonight.

Lol watch that miss too

[Snowman67]

I am guessing this one becomes Harvey and the 92l becomes Irma. Irma, that name sounds creepy!

I am not a fan of the "I" named storms

You and me both. Ike did a number on us. Had a big bull pine fall on the house...