97L growing more organized, will bring heavy rain to the Lesser Antilles

By: Dr. Jeff Masters , 3:55 PM GMT on July 19, 2009

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The tropical wave near 12N 52W, about 600 miles east of the Lesser Antilles Islands (97 L), has grown more organized this morning as it tracks west at about 20 mph. This wave is surrounded by an area of very dry air from the Sahara Desert, but 97L has been able to steadily moisten a large region of the atmosphere over the past day, insulating itself from the dry air. This moistening process has been aided by sea surface temperatures (SSTs) that have steadily increased from 26.5°C to 27.5°C, plus the presence of only 10 knots of wind shear. The system now has a small area of intense thunderstorms near its center, with some rotation of the cloud pattern evident at mid-levels of the atmosphere. An upper-level outflow channel has opened to the north, and there is evidence that surface spiral bands are beginning to form. This morning's QuikSCAT pass missed 97L, so we don't know what is happening at the surface.

Wind shear is a modest 10 knots over the disturbance, and is forecast to remain in the moderate 10 - 15 knot range through Monday morning. This should allow further development to occur today, and 97L could be approaching tropical depression strength on Monday as it moves through the central Lesser Antilles Islands. Monday night, shear is expected to rise to 20 - 30 knots, thanks to the presence of a trough of low pressure at upper levels of the atmosphere over the eastern Caribbean. Since 97L is a relatively small system, it is very vulnerable to wind shear. This shear may be able to drive some of the dry air west of 97L deep into its interior, significantly disrupting the disturbance. Shear will remain high along 97L's path through Thursday, when the storm should be in the western Caribbean near Cuba. If there is anything left of 97L by then, some development is possible. The National Hurricane Center gave 97L a low (less than 30% chance) of developing into a tropical depression in the next 48 hours in their 8am Tropical Weather Outlook. However, I'd say the odds are now in the medium range (30 - 50%).

None of the computer models are forecasting tropical storm development over the next seven days.


Figure 1. Current satellite image of African wave 97L.

I'll have an update Monday morning. As 97L approaches the islands, you may want to follow local observations there using our wundermap for 97L.

Jeff Masters

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New Map
Member Since: May 16, 2009 Posts: 1 Comments: 1231
2014. Patrap
Floater 1 AL97 AVN Color Imagery Loop

Member Since: July 3, 2005 Posts: 426 Comments: 128645
Quoting Tazmanian:
whats take this time too say a few words too are be loveing dead 97L it put up a good fight and the wind shear has won the fight


you tend to write things off before they are actually gone, seems you do it a lot as well
whats take this time too say a few words too are be loveing dead 97L it put up a good fight and the wind shear has won the fight
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Even though wind shear has now begun to clearly impact the system, I'm not going to count it out. Been a fighter all throughout its lifetime, so I can't underestimate it. Just going to sit back and watch...starting tomorrow AM. Have a good night y'all and be civil.
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Taz have u been hittin the sauce, it isnt dead.
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Quoting moonlightcowboy:
History Channel "That's Impossible" - Tuesday at 9:00 pm cst.

Episode - "Weather Warfare"

The power to use tornados, hurricanes and the deadliest weather as weapons of war may now be possible. We'll investigate reports that weather weapons are in development and reveal the technology that--in the future--could turn hurricanes, earthquakes, even tsunamis into some of the most powerful and plausibly deniable weapons of mass destruction the world has ever seen.


Sigh. :( Why don't they use all that intellect and power and money for peace. Add plausible deniability and whoever uses it can never be blamed. Sorry. Just caught my eye. Back to Mother Nature's weather. Is this shear the end of the little storm that could?
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this time its rip up for good by the wind shear
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Taz ripped apart now?
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Quoting Tazmanian:
say good bye too 97L all it was a good little fighter but has you can see wind shear has rip it a part


You have said that each of the last 3 nights too and well its still around
say good bye too 97L all it was a good little fighter but has you can see wind shear has rip it a part
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burned after posting, u must have missed my wonderful description about how all that is a haircut!! The heart is farther south. That is what i meant where convection was blowing up. u see i dont know jack about how a hurricane developes, but i do see how 97 invest is rolling like a bowling ball towards the carrib, and its going to take more than a puff of wind to blow it out!!! LOL
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Quoting Tazmanian:

LOL any one home


Lol. I'm waiting until CIMSS
Member Since: May 16, 2009 Posts: 1 Comments: 1231

LOL any one home

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17 mins till CIMSS update
Member Since: May 16, 2009 Posts: 1 Comments: 1231
Look at the shf5. That's a big jump lol.
Link
Member Since: May 16, 2009 Posts: 1 Comments: 1231
1999. 7544
thanks ww pat ur link no working
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Here is a pic; it is clearly being sheared

Quoting Patrap:


They time out after 60secs,..so heres da page.
Contact Me


Tropical Cyclone Model Guidance

thanks
Member Since: May 16, 2009 Posts: 1 Comments: 1231
1996. Patrap
Quoting weatherwatcher12:

It says access forbidden


They time out after 60secs,..so heres da page.


Tropical Cyclone Model Guidance
Member Since: July 3, 2005 Posts: 426 Comments: 128645
Quoting Patrap:
Early-cycle intensity guidance AL97

still says access forbidden
Member Since: May 16, 2009 Posts: 1 Comments: 1231
1994. Patrap
Quoting weatherwatcher12:

It says access forbidden


They time out after 60secs,..so heres da page.


Tropical Cyclone Model Guidance
Member Since: July 3, 2005 Posts: 426 Comments: 128645
Quoting 0741:
ok because alot come in here to get information we donot need those think their pro weatherman we all need go by nhc say and national weather service say


I understand since they are the real experts and the people in charge. What my purpose is when creating those graphics and explanations is to try and offer people an easier perspective as to whats going on and try my best to provide easy-to-understand explanations since I know that some people who access this site don't have a deep meteorological background. In no way and shape do I intend to overrule the government-run agencies like the NHC and NWS.
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1992. Patrap
Early-cycle intensity guidance AL97
Member Since: July 3, 2005 Posts: 426 Comments: 128645
Quoting moonlightcowboy:
"That's Impossible" - Tuesday at 9:00 pm cst.
what is?
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It only matters what u look at? lol
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1989. KEEPEROFTHEGATE (Mod)
well iam gone adios got work in the am later all been a slice
Member Since: July 15, 2006 Posts: 173 Comments: 54353
Quoting Patrap:
AL97 Early Track Guidance


It says access forbidden
Member Since: May 16, 2009 Posts: 1 Comments: 1231
Quoting stormsurge39:
burned after posting, what satt are u looking at?


doesnt matter which you look at, it is again very clear that the small ball of convection is getting sheared
History Channel "That's Impossible" - Tuesday at 9:00 pm cst.

Episode - "Weather Warfare"

The power to use tornados, hurricanes and the deadliest weather as weapons of war may now be possible. We'll investigate reports that weather weapons are in development and reveal the technology that--in the future--could turn hurricanes, earthquakes, even tsunamis into some of the most powerful and plausibly deniable weapons of mass destruction the world has ever seen.
Member Since: July 9, 2006 Posts: 184 Comments: 29610
1985. Patrap
AL97 Early Track Guidance

Member Since: July 3, 2005 Posts: 426 Comments: 128645
1984. KEEPEROFTHEGATE (Mod)
Quoting stormdude77:


Barbados, 97L is just a few miles to my east...
ya got weather moving in from the ne
Member Since: July 15, 2006 Posts: 173 Comments: 54353
burned after posting, what satt are u looking at?
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Quoting 7544:
hi everyone is this latest model runs or old ones thanks Link

some are new some are old. The ones that say 00z are new
Member Since: May 16, 2009 Posts: 1 Comments: 1231
The farmer fed him through an eye dropper
Quoting stormdude77:


Barbados, 97L is just a few miles to my east...
oh ok
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1979. 7544
hi everyone is this latest model runs or old ones thanks Link
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Quoting TampaMishy:
Where are you?


Barbados, 97L is just a few miles to my east...
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its far enough S not to get totally killed by shear.
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Quoting BurnedAfterPosting:
actually Mishy they found that he did not suffer at all, he was able to function normally and was quite healthy
How did he eat?
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Quoting stormdude77:
It's starting to rain here and the wind is also picking up....
Where are you?
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1974. KEEPEROFTHEGATE (Mod)
later mlc iam going soon as well work in the am
Member Since: July 15, 2006 Posts: 173 Comments: 54353
.
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1972. KEEPEROFTHEGATE (Mod)
Quoting StSimonsIslandGAGuy:
I think 97L is no threat for at least 3 days. If it survives, maybe then. But not for now.
barbados will or already starting to feel the effects in thunder showers gusty winds and increase as they move to wards the paling of the sky
Member Since: July 15, 2006 Posts: 173 Comments: 54353
Quoting KEEPEROFTHEGATE:
what vortex or the headless chicken
Oh jeez!
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actually Mishy they found that he did not suffer at all, he was able to function normally and was quite healthy
Quoting stormsurge39:
Stormchaser does it look like on satt that the shear is lifting some, and is relaxing a little? Also look at that ball of convection right at the center.This invest is not ready to be riiiiped yet!


that ball of convection is being heavily sheared right now, shear looks to be getting stronger, not relaxing
...ooops, gotta go - IceRoad Truckers is on! LOL.

Catch you later on, Keep!

...been fun, all!
Member Since: July 9, 2006 Posts: 184 Comments: 29610
It has pockets of deeping conveciton/not even reached dmax yes.wait till more convection explodes.
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Quoting Vortex95:


That was actually his name, well at least his stage name. He was also called Miricle Mike.
I believe you but find it inhumane that an animal lived such a way. Also I forgot whose analogy on the buzz cut but, could one!
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Where is the Oz GFS
Member Since: May 16, 2009 Posts: 1 Comments: 1231

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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