Tropical Storm Henri forms

By: Dr. Jeff Masters , 9:37 PM GMT on October 06, 2009

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The tropics spawned another October surprise today, when Tropical Storm Henri formed in the face of adverse levels of wind shear. Henri is under about 20 - 25 knots of wind shear, which ordinarily prevents rapid development like we witnessed this afternoon. However, the environment is quite moist, and Henri is over warm waters, 29°C. An ASCAT pass from 11:37am EDT showed Henri had winds of 40 mph. Satellite loops show that Henri has managed to rapidly develop a large area of intense thunderstorms with cold cloud tops in just a few hours, though the high shear is keeping any thunderstorms from developing on the west side of the center. Water vapor satellite images show that there is some dry air to Henri's northwest, and this dry air will act to slow Henri's growth some. The dry air is creating strong downdrafts that are apparent on visible satellite images as arcs of cumulus clouds spreading out from where the downdraft hits the ocean surface, along the northwest side of Henri's center.

None of the reliable global computer models showed Henri would develop, and the models all favor weakening and dissipation of Henri by Thursday, due to high wind shear of 20 - 25 knots. The official NHC forecast goes along with this scenario, but think there is a medium (30 - 50% chance) that Henri will not dissipate. By Friday, wind shear in the vicinity of Henri (or its remains) is predicted to fall to the low to moderate range. Even if Henri has dissipated by that point, regeneration into a tropical storm may occur. The track of Henri after Friday is problematic, as the storm will be in an area of weak steering currents. Several of the models favor a track to the west-southwest into the Caribbean, across Hispaniola. Residents of the Dominican Republic and Haiti should anticipate that Henri or its remains may bring flooding rains to Hispaniola by Saturday. It is also possible that Henri will get pulled northwards and recurved out to sea, and not affect the Caribbean at all, though.


Figure 1. Latest satellite image of Henri.

A little tropical weather for England
The remnant circulation of Tropical Storm Grace is currently making landfall in Southwest England. Grace's remains brought sustained winds of tropical storm force--41 mph--to one buoy off the coast last hour, and 38 mph to the Sevenstones Lightship buoy. you can track the progress of Grace via our wundermap for the region.


Figure 2. The remnant circulation of Tropical Storm Grace scoots by to the south of Ireland in this visible satellite image taken at 1pm EDT 10/06/09. Image credit: UK Met Office.

Jeff Masters


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And also for participants and lurkers Henri is pronounced Ah-n-ree.

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yeah i thought you wouldn't take that well, sorry that was kinda mean. ;(
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Quoting JLPR:


we on the blackout so the SSD pictures are 2hrs old


I realize that but the loop from then shows a very exposed Henri....i doubt much has changed when looking at the shear.
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Quoting TampaSpin:


The center is now a naked swirl to the SW of the convection...you can see it on RGB mode zoomed in.......Link


Thanks for the image link, TS.

Naked swirl is a good description. To the 'Naked Eye' he looks like he wants to organize.
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503. JLPR
Quoting TampaSpin:


The center is now a naked swirl to the SW of the convection...you can see it on RGB mode zoomed in.......Link


we on the blackout so the SSD pictures are 2hrs old
Member Since: September 4, 2007 Posts: 36 Comments: 5223
502. Prgal
000
ABNT20 KNHC 070531
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT WED OCT 7 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM HENRI...LOCATED ABOUT 510 MILES EAST OF THE NORTHERN
LEEWARD ISLANDS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

PUBLIC ADVISORIES ON HENRI ARE ISSUED UNDER WMO HEADER WTNT35 KNHC
AND UNDER AWIPS HEADER MIATCPAT5. FORECAST/ADVISORIES ON HENRI ARE
ISSUED UNDER WMO HEADER WTNT25 KNHC AND UNDER AWIPS HEADER
MIATCMAT5.

$$
FORECASTER KIMBERLAIN
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I'm out good nite everyone. This blog gets harder to come to each day with the crap that gets posted.
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Quoting TampaSpin:
ORCA is very good at posting on his blog everyone else's work that it performed instead of posting something himself. But, yet he tries his best to critize others. He's an amazing copy and post blogger. I give him all the prompts!


TS Henri looks good, considering 25KT of SW shear.

Catfight on aisle 7, LOL!!
Member Since: August 25, 2009 Posts: 20 Comments: 6785
Quoting JLPR:
impressive
now, the question is: where is the LLC? xD
underneath, to the west or on the edge of the convection


The center is now a naked swirl to the SW of the convection...you can see it on RGB mode zoomed in.......Link
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498. xcool
guess Henri have kids !
Member Since: September 26, 2009 Posts: 2 Comments: 15684
497. xcool
lol
Member Since: September 26, 2009 Posts: 2 Comments: 15684
496. JLPR
Also the band of convection seems to have separated from Henri... weird =P
Member Since: September 4, 2007 Posts: 36 Comments: 5223
493. JLPR
impressive
now, the question is: where is the LLC? xD
underneath, to the west or on the edge of the convection
Member Since: September 4, 2007 Posts: 36 Comments: 5223
492. xcool



oh oh bigggg
Member Since: September 26, 2009 Posts: 2 Comments: 15684
Quoting JerseyFisher:


Graphs, images and analysis is what we want!!



Thats is what everyone wants that visits my sight with any true intentions.....Unlike some that just love to try destroy this blog!
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Since Henri is the odd name storm atm. Odd fact, when i heard Hurricane Georges, I heard being pronounced on TV as Jhorge.
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489. xcool
If the shear relaxes we may have a hurricane on are hands imo
Member Since: September 26, 2009 Posts: 2 Comments: 15684
You guys have fun... looks like things are off track for awhile.. later
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting ElConando:
Tampa not to offend but some people cannot read your blog usually has SOOOO MANY PICTURES that it freezes the computer. Mine doesn't have the problem usually but from time to time, even mine has issues with it.


Graphs, images and analysis is what we want!!

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485. xcool
WeatherStudent lol
Member Since: September 26, 2009 Posts: 2 Comments: 15684
484. xcool
ElConando no
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xcool are you iceman555?
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Quoting ElConando:


Actually its a blog controlled by Weather Student. Thats why he has never been banned.


I was trying to figure out what he was talking about also... why would he say that Dr Masters Blog is not a weather Blog?
Member Since: October 1, 2007 Posts: 81 Comments: 26511
480. xcool
ElConando haha lmaoooooo
Member Since: September 26, 2009 Posts: 2 Comments: 15684
Tampa not to offend but some people cannot read your blog usually has SOOOO MANY PICTURES that it freezes the computer. Mine doesn't have the problem usually but from time to time, even mine has issues with it.
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477. xcool
TampaSpin.lmao
Member Since: September 26, 2009 Posts: 2 Comments: 15684
Quoting TampaSpin:


Are you kidding all you post is humor....i didn't know this was a weather blog.


Actually its a blog controlled by Weather Student. Thats why he has never been banned.
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Quoting TampaSpin:


Thanks i guess you read it instead of others that apparently don't read and just try to make a laugh of things like some blogs are that post the humor of the day reports...if you know what i mean.


No I read you quite often infact. I trust experts, always have, always will.
Thanks again. Keep on keeping on.
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Quoting reedzone:


It needs to gain some latitude before it really becomes something to watch, thought it was just interesting to note the anticyclone forming on it.


Agreed, but I don't think its going to happen. Its to far south.
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting Orcasystems:


I have been looking at that area... but do not the steering currents limit it in sea room to develop?


It needs to gain some latitude before it really becomes something to watch, thought it was just interesting to note the anticyclone forming on it.
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Quoting Orcasystems:


I have been looking at that area... but do not the steering currents limit it in sea room to develop?


Are you kidding all you post is humor....i didn't know this was a weather blog.
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471. xcool



Member Since: September 26, 2009 Posts: 2 Comments: 15684
Quoting reedzone:
The area southwest of Henri is interesting, also has a developing Anticyclone. Where's the donwcasters that said Henri would dissipate or look bad by now? Seriously.. I want know where they are at!


I have been looking at that area... but do not the steering currents limit it in sea room to develop?
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting Orcasystems:


ROFL, does he have a yellow circle also?


Over his head yes, may he R.I.P.
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keep up the good work TS, will check back for a Henri update in the am
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Quoting ElConando:


Then you don't know Bo Diddley



ROFL, does he have a yellow circle also?
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting JerseyFisher:
Thanks for the good reporting Tampaspin



Thanks i guess you read it instead of others that apparently don't read and just try to make a laugh of things like some blogs are that post the humor of the day reports...if you know what i mean.
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Thanks for the good reporting Tampaspin

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The area southwest of Henri is interesting, also has a developing Anticyclone. Where's the donwcasters that said Henri would dissipate or look bad by now? Seriously.. I want know where they are at!
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this quuiet season has been great for the beaches
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out like a lion.... hoping Henri is just a wittle puddy tat!
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453. I can see why it is strengthening.
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Quoting Orcasystems:


I see nothing there..diddly?


No KIDDING......LMAO
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Quoting ElConando:


its a glory ho- I mean special place.


I see nothing there..diddly?

Member Since: October 1, 2007 Posts: 81 Comments: 26511

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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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