Invest 99L in Eastern Caribbean Thread #5

[HURAKAN]

haha, thanks Hurakan, no I decided to go into biomedical research.

That's better for humanity and for the world!!!

[Thunder44]

12N/61W is east of the Caribbean Sea (see my chart above). There's no low OR wave axis there, it's in the Caribbean. I wonder who wrote this?

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU AUG 02 2007

...SPECIAL FEATURES...
A 1011 MB LOW PRESSURE CENTER IS NEAR 12N61W...MOVING WEST
10 KT. THIS LOW PRESSURE HAS BEEN WEAKENING LITTLE BY LITTLE
AND HAS BECOME AN OPEN TROPICAL WAVE AT THIS POINT BY
02/0900 UTC. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS FROM
12N TO 15N BETWEEN 62W AND 67W. THERE ARE NO SIGNS OF TROPICAL
CYCLONE FORMATION AT THIS TIME. THE SYSTEM STILL HAS SOME
POTENTIAL TO BECOME A TROPICAL DEPRESSION DURING THE NEXT
DAY OR SO AS IT CONTINUES MOVING WESTWARD NEAR 20 MPH.
A RECONNAISSANCE PLANE WILL INVESTIGATE THE AREA AGAIN
LATER TODAY IF NECESSARY.


Yep....just an open wave.

I think they are basing it off a 6z analysis. Which is almost 6 hours ago:

http://www.nhc.noaa.gov/tafb/ATSA_06Z.gif

[HURAKAN]

02/0545 UTC 12.4N 61.0W T1.0/1.0 99L

I think they are basing it on the last Dvorak, which was 6 hours ago.

[marcane_1973]

I was trying to figure out why they start out saying

..MOVING WEST 10 KT.

Then ends with

CONTINUES MOVING WESTWARD NEAR 20 MPH

I thought 10KT~=12MPH

The TWD is wrong because the system is already at 65W.

Oh Dear God!!! Look what Bill Proenza has done to our wonderfull staff at the NHC. J/K J/K I had to say it.

[vaffie]

I can't wait to see what recon finds in 4 hours. I think even I'm gonna be surprised.

[skysummit]

I can't wait to see what recon finds in 4 hours. I think even I'm gonna be surprised.

You think? What are YOU expecting them to find?

[vaffie]

I can't wait to see what recon finds in 4 hours. I think even I'm gonna be surprised.

You think? What are YOU expecting them to find?

I'm expecting them to find a pressure of 999 mb by then and winds of 45-50 mph--a rapidly deepening tropical storm.

[HURAKAN]

Oh Dear God!!! Look what Bill Proenza has done to our wonderfull staff at the NHC. J/K J/K I had to say it.

WOW, that was good. LOL, seriously.

Damn you Proenza!!!! j/k

[HURAKAN]

I can't wait to see what recon finds in 4 hours. I think even I'm gonna be surprised.

You think? What are YOU expecting them to find?

I'm expecting them to find a pressure of 999 mb by then and winds of 45-50 mph--a rapidly deepening tropical storm.

You're optimistic. The truth is that as of now, there is not evidence from satellite images, land obs, ship ob, or anything that shows a LLC. Just an impressive area of convection that may develop a LLC.

[Thunder44]

12N/61W is east of the Caribbean Sea (see my chart above). There's no low OR wave axis there, it's in the Caribbean. I wonder who wrote this?

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU AUG 02 2007

...SPECIAL FEATURES...
A 1011 MB LOW PRESSURE CENTER IS NEAR 12N61W...MOVING WEST
10 KT. THIS LOW PRESSURE HAS BEEN WEAKENING LITTLE BY LITTLE
AND HAS BECOME AN OPEN TROPICAL WAVE AT THIS POINT BY
02/0900 UTC. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS FROM
12N TO 15N BETWEEN 62W AND 67W. THERE ARE NO SIGNS OF TROPICAL
CYCLONE FORMATION AT THIS TIME. THE SYSTEM STILL HAS SOME
POTENTIAL TO BECOME A TROPICAL DEPRESSION DURING THE NEXT
DAY OR SO AS IT CONTINUES MOVING WESTWARD NEAR 20 MPH.
A RECONNAISSANCE PLANE WILL INVESTIGATE THE AREA AGAIN
LATER TODAY IF NECESSARY.


Yep....just an open wave.

I think they are basing it off a 6z analysis. Which is almost 6 hours ago:

http://www.nhc.noaa.gov/tafb/ATSA_06Z.gif

The usually the write the TWDs based on a surface analysis done about 5 or 6 hours before it gets sent out. So the next TWD at 2:05pm will be based on a 12z surface analysis.

[vaffie]

You're right--I'm optimistic--but I wouldn't be that surprised judging from the last few hours of satellite pictures if I was actually conservative.

You're optimistic. The truth is that as of now, there is not evidence from satellite images, land obs, ship ob, or anything that shows a LLC. Just an impressive area of convection that may develop a LLC.

[schurricaneinfo]

Definitely some convection starting to fire up by looking at the loop. Looks like this thing might be starting to get cranked up.

[tailgater]

You're right--I'm optimistic--but I wouldn't be that surprised judging from the last few hours of satellite pictures if I was actually conservative.

You're optimistic. The truth is that as of now, there is not evidence from satellite images, land obs, ship ob, or anything that shows a LLC. Just an impressive area of convection that may develop a LLC.

Pressure would have drop like a rock, winds are possible.
Bouy south PR

http://www.ndbc.noaa.gov/station_page.php?station=42059

[punkyg]

It looks so pretty in both loops.

http://www.ssd.noaa.gov/goes/flt/t2/loop-avn.html

http://www.ssd.noaa.gov/goes/flt/t2/loop-rb.html


Don't know why, but when i saw this around 7am first thing that came to my mind was tropical storm chris from last year weird huh.

[Derek Ortt]

why is everyone assuming that recon is flying? Since the obs are fairly conclusive, it would not surprise me to learn that recon is cancelled

[Chacor]

[vaffie]

Pressure would have drop like a rock, winds are possible.
Bouy south PR
http://www.ndbc.noaa.gov/station_page.php?station=42059

With a rapidly deepening system, pressure falls and wind increases at the periphery are delayed by two or three hours. That buoy is not even under the convection yet (which has a maximum radius of 200 miles).

[HURAKAN]

why is everyone assuming that recon is flying? Since the obs are fairly conclusive, it would not surprise me to learn that recon is cancelled

That cannot be assumed until confirmation or cancellation by the NHC.

[skysummit]

why is everyone assuming that recon is flying? Since the obs are fairly conclusive, it would not surprise me to learn that recon is cancelled

I guess because that's the last notice we've received, and won't know if it's cancelled for a couple more hours or so, however, we all know what assuming does.

[Hyperstorm]

We can't say this is a rapidly deepening tropical storm at this time. There is the most important ingredient missing...a defined low-level center.

As expected, the tropical wave has not developed over the past couple of days due to the marginal environment it's been embedded in. The system surely, though still has potential for development over the next 24-48 hours. Once it gets to the point SW of Puerto Rico and on westward, we could begin to see improved organization. Of course, we need the system to do one thing first. It needs to slow down! With the fast forward motion, it will have less time to strengthen over the very warm waters of the Caribbean Sea and it will have a tough time developing a west wind.

We have one major thing going for its development right now, and that is the explosive development of thunderstorms. That usually will lead to a development of a LLC, but only if it can slow down. This process usually takes about 24 hours, so tomorrow we could easily be talking about tropical storm Dean, again IF it slows down even 5 mph. The slower forward speed would also keep it from the strongest upper-level southerly shear associated with the upper-level low developing over the western Caribbean Sea. The ULL is moving westward, but so is the system and if it doesn't slow down, it will cut it to pieces. As a matter of fact, latest satellite imagery indicates southerly shear beginning to impact the SW periphery of this persistent disturbance.

Will be a very interesting couple of days coming up...I'll be watching.