Tropical Storm Henri forms

By: Dr. Jeff Masters , 21:37 GMT le 06 octobre 2009

Share this Blog
3
+

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


Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 157 - 107

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14Blog Index

157. JLPR
so to what conclusion do we get from this


Where is Henri's LLC? xD
Member Since: 4 septembre 2007 Posts: 36 Comments: 5223
imaged centre directly overhead at 18n/55w

storm

010L/TS/H



WIDE SHOT DIRECTLY OVERHEAD
Member Since: Posts: Comments:
Quoting GeoffreyWPB:
A little intensifying?

And moving westward?
Member Since: Posts: Comments:
Quoting SouthALWX:

Good anticyclonic flow over it looks like.. wouldn't surprise me if it pulled into the SE caribbean. As you said, it really needs some cyclonic turning at the surface and a lowering in pressure to make that happen though.


It certainly has a superior environment compared to Henri but systems that far S lack the assist from the Coriolis effect to start " spinning ". I know that they can organise even that far S but it takes a lot longer and this wave is already close to SA.

Have to work on dinner now but will be back later.
Member Since: Posts: Comments:
A little intensifying?

Member Since: Posts: Comments:
Quoting amd:


the latest steering trends look like a more westward movement for now.

Latest West Atlantic Steering

Notice how Henri is now embedded in the east to west flow, instead of being next to the weakness.


Not good
Member Since: 6 octobre 2007 Posts: 0 Comments: 6142
Quoting kmanislander:


Sorry, I was getting a few baby backs ready for the smoker grill LOL

That wave looks to be destined for South America and would need to start pulling up to the WNW very soon in order to enter the Caribbean.

If it develops a low pressure center that would help to change the current track but for now, being that far S means it is still caught up in the ITCZ and unlikely to develop.

Good anticyclonic flow over it looks like.. wouldn't surprise me if it pulled into the SE caribbean. As you said, it really needs some cyclonic turning at the surface and a lowering in pressure to make that happen though.
Member Since: Posts: Comments:
Retired Hurricane Names
Member Since: Posts: Comments:
147. amd
Quoting jurakantaino:
It seems to be moving west, I mean more west than WNW.


the latest steering trends look like a more westward movement for now.

Latest West Atlantic Steering

Notice how Henri is now embedded in the east to west flow, instead of being next to the weakness.
Member Since: Posts: Comments:
Quoting CosmicEvents:
Was Georges(pronounced zhoarsh btw..lol) retired?


Georges was definitely retired and replaced by Gaston.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
Quoting superpete:
Kman:What is your opinion of the wave currently centred at 8N 47W,heading west?Looks like it may make it into the Se Carib'.


Sorry, I was getting a few baby backs ready for the smoker grill LOL

That wave looks to be destined for South America and would need to start pulling up to the WNW very soon in order to enter the Caribbean.

If it develops a low pressure center that would help to change the current track but for now, being that far S means it is still caught up in the ITCZ and unlikely to develop.
Member Since: Posts: Comments:
Ivan was the one that opened my eyes to say the least!
Member Since: Posts: Comments:
Was Georges(pronounced zhoarsh btw..lol) retired?
Member Since: Posts: Comments:
It seems to be moving west, I mean more west than WNW.
Member Since: Posts: Comments:
141. JLPR
Quoting Weather456:


Here's a thought, the two that dissipate 10L are global models, which never developed 91L in the first place, while the statistical models showed it becoming a tropical storm.


maybe Henri will pull an Erika and ignore the models =P
Member Since: 4 septembre 2007 Posts: 36 Comments: 5223
Quoting Weather456:
I picked out several locations and the respective probability of being affected by Henri

Puerto Rico - 20-30%
Hispaniola - 40-50%
Florida Keys/Florida - 30%
Cuba - 30-40%
Texas Coast - less than 5%


Thanks for your thoughts. I do live in Texas and while I dont wish a storm on anyone, I certainly hope the odds hold in our favor
Member Since: Posts: Comments:
Ivan was RETIRED! Replaced by Igor.
Member Since: 25 août 2009 Posts: 20 Comments: 6785
Quoting pcolasky:


Ivan was retired right?



If it wasn't it should have been. Lord knows everybody I know got "IVANIZED".
Member Since: Posts: Comments:
Quoting pcolasky:


Ivan was retired right?


correct, he, Charley, Frances and Jeanne.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
Quoting all4hurricanes:
I know this is an el nino year and I know there have been short storms and I know this year beat out the extremists that said this season would end in Sept, but Danny and Erica are some of the ugliest storms I've ever seen Danny was never organized, it pained me just to watch it. 2009 so far has been my least favorite tracking season.


TS Danny & Erika tried but could never get it going, shear and troughs. Not trying to be sarcastic, this season is real annoying, but the shear made them look like different zoo animals :0).
Member Since: 25 août 2009 Posts: 20 Comments: 6785
Quoting Weather456:
Next hurricane season will be a bit more interesting, probably for a good while. The names and calendar dates are the same as 2004, except for the 4 that were retired. For example, Alex starts of the season with Friday August 13 2010 in the mix. Some dejavus next year.


Ivan was retired right?
Member Since: Posts: Comments:
Quoting kmanislander:
I am still curious to see the Quikscat pass this evening to see if there is a closed low with Henri.

With all that shear it would not surprise me to see the low open to the SW.
Kman:What is your opinion of the wave currently centred at 8N 47W,heading west?Looks like it may make it into the Se Carib'.
Member Since: Posts: Comments:
Quoting Weather456:
Next hurricane season will be a bit more interesting, probably for a good while. The names and calendar dates are the same as 2004, except for the 4 that were retired. For example, Alex starts of the season with Friday August 13 2010 in the mix. Some dejavus next year.
Let's hope not lost My enough in 2004 with Frances and Jeanne
Member Since: Posts: Comments:
Next hurricane season will be a bit more interesting, probably for a good while. The names and calendar dates are the same as 2004, except for the 4 that were retired. For example, Alex starts of the season with Friday August 13 2010 in the mix. Some dejavus next year.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
Quoting thegoldenstrand:


Thanks! It seems to have potential to head further west, I was wondering if it could develop like Grace did.


next name is Ida, replaced Isabel.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
Atlantic Hurricane Season 2009

"The year of shear, year of surprises, year the NHC wants to forget (POOR computer models) AND the year isn't over yet"!!
Member Since: 25 août 2009 Posts: 20 Comments: 6785
844

WHXX04 KWBC 062315

CHGQLM

ATTENTION...NATIONAL HURRICANE CENTER



NCEP COUPLED GFDL HURRICANE MODEL FORECAST MADE FOR



TROPICAL STORM HENRI 10L

DISCLAIMER ... THIS INFORMATION IS PROVIDED AS GUIDANCE. IT

REQUIRES INTERPRETATION BY HURRICANE SPECIALISTS AND SHOULD

NOT BE CONSIDERED AS A FINAL PRODUCT. PLEASE SEE THE TPC/NHC

OFFICIAL FORECAST.





FORECAST STORM POSITION



HOUR LATITUDE LONGITUDE HEADING/SPEED(KT)



0 17.4 53.5 300./17.1

6 18.1 54.3 312./10.1

12 18.0 56.7 268./22.7

18 18.4 57.9 285./12.3

24 18.8 59.2 287./12.3

30 19.2 60.9 283./16.9



STORM DISSIPATED AT 30 HRS AT THE ABOVE PSN.
Member Since: Posts: Comments:
Quoting Weather456:


tropical wave. Dr. Lyons mentioned it. to move through the southern Antilles through the next days and as everything, it will be monitored.


Thanks! It seems to have potential to head further west, I was wondering if it could develop like Grace did.
Member Since: Posts: Comments:
Quoting PensacolaDoug:


Being as Henri is french, he'll prolly "surrender" to the shear.


I don't think so. Looks like he's been putting up quite a fight over the last day or two.

I don't want to see Henri cause any problems anywhere! But the computer models this year, are doing a real lousy job!!!
Member Since: 25 août 2009 Posts: 20 Comments: 6785
Quoting PensacolaDoug:


Being as Henri is french, he'll prolly "surrender" to the shear.


Georges was French also.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
I know this is an el nino year and I know there have been short storms and I know this year beat out the extremists that said this season would end in Sept, but Danny and Erica are some of the ugliest storms I've ever seen Danny was never organized, it pained me just to watch it. 2009 so far has been my least favorite tracking season.
Member Since: 29 Mars 2008 Posts: 0 Comments: 2370
Hurricane models continue to dissipate Henri which certainly would not be surprising as the system gets closer to an upper level trough.
Member Since: Posts: Comments:
Quoting thegoldenstrand:


what is the circle of clouds to the southeast of Henri? Is it a low, a wave or just a coincidence of a circle of clouds?


tropical wave. Dr. Lyons mentioned it. to move through the southern Antilles through the next days and as everything, it will be monitored.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
Quoting tropics21:
Henri is French for Henry She is a He


Being as Henri is french, he'll prolly "surrender" to the shear.
Member Since: Posts: Comments:
Tropical Storm Grace formed just northeast of the Azores on October 4 out of a previously non-tropical storm. It is the farthest-northeast-forming tropical storm in the Atlantic in the satellite era, breaking Vince's record from 2005.[24] It moved rapidly northwards, reaching peak winds of 70 mph (110 km/h) early on October 5 and was absorbed by a frontal system late that same day, while located less than 100 miles from the southwestern coast of Ireland.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
Quoting hunkerdown:
yet you are sitting there posting grammar lessons that truly looks idiotic

Idiotic? I would say that trivial, or picayune, would be better choices of adjectives to describe my little addition in pronounciation(not grammar). The prevailing school of thought would say that anything that one learns is a positive, at least for people who appreciate gaining knowledge, not for idiots though.
Again..it's aaahhhhnh-ree!
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:


latest wv image tropical atl.


what is the circle of clouds to the southeast of Henri? Is it a low, a wave or just a coincidence of a circle of clouds?
Member Since: Posts: Comments:
Quoting tropics21:
Henri is French for Henry She is a He


Oops! Honest, TS Henri has enough to deal with, ya' know, wind shear, some dry air in the NW quadrant, my bad.

Member Since: 25 août 2009 Posts: 20 Comments: 6785
Quoting Bordonaro:
I've got this "gut" feeling that shear is NOT going to kill TS Henri. She appears to be a fighter like Danny, Erika & Fred.

I'd keep a close eye on Henri, she may surprise everyone, warm SST's can do amazing things....shear or no shear...she has plenty of moist atmosphere to work with.
Henri is French for Henry She is a He
Member Since: Posts: Comments:
Quoting Weather456:


I was thinking something today. There are so many people out there that don't like tropical storms yet they come to the blog where you must see some mentioned of tropical storm activity. I never understood that logic. For example, I hate politics so you would not find me on a political blog. I'm not a big fan of global warming thus you would not see on a GW blog.


Weather456, those who get in here and try to start 4 yr old childish games saying, " I hate Tropical systems but I come here to get a bloggers point of view ", are absolutely in DENIAL! They're afraid to admit their love of the power of the atmosphere. Such poor souls indeed!

Ya' know, like an alcoholic who says, I don't have a drinking problem"!
Member Since: 25 août 2009 Posts: 20 Comments: 6785
Wow. I stay away for a few hours and look what happens. Hello Henri. Now go out to sea. Those Islands have been through enough. They don't want your rains. Now if he'll just listen to me.
Member Since: Posts: Comments:
Quoting AllStar17:


Well, the NHC continues to baffle me.


Me, personally I agree with the NHC out 3 days, but I'm not entirely buying dissipation. I was thought never readily jump to conclusions with models and this is why:

yesterday


There is a band of upper shear that continues to linger just to its northwest and north and may cause some problems in the near term, however, the upper environment is forecast to improve in the long-term by most reliable models, despite them not compensating for a change in strength. Only the statistical intensity guidance bring 91L to a tropical storm within 5 days which is entirely possible given the shear forecast.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
113. xcool



Member Since: 26 septembre 2009 Posts: 2 Comments: 15648
18Z GFDL Henri


HOUR: .0 LONG: -53.53 LAT: 17.43 MIN PRESS (hPa): 1009.19 MAX SURF WIND (KNOTS): 38.34
HOUR: 6.0 LONG: -54.30 LAT: 18.12 MIN PRESS (hPa): 1007.23 MAX SURF WIND (KNOTS): 61.08
HOUR: 12.0 LONG: -56.69 LAT: 18.04 MIN PRESS (hPa): 1010.83 MAX SURF WIND (KNOTS): 41.07
HOUR: 18.0 LONG: -57.94 LAT: 18.37 MIN PRESS (hPa): 1012.31 MAX SURF WIND (KNOTS): 42.47
HOUR: 24.0 LONG: -59.18 LAT: 18.75 MIN PRESS (hPa): 1012.52 MAX SURF WIND (KNOTS): 41.98
HOUR: 30.0 LONG: -60.92 LAT: 19.16 MIN PRESS (hPa): 1014.34 MAX SURF WIND (KNOTS): 35.23
Member Since: Posts: Comments:
Quoting Weather456:


Here's a thought, the two that dissipate 10L are global models, which never developed 91L in the first place, while the statistical models showed it becoming a tropical storm.


Well, the NHC continues to baffle me.
Member Since: 29 juin 2009 Posts: 13 Comments: 5311
Quoting StormW:
Evening,
Just on real quick.
Good Evening Storm W hope Your Day went well
Member Since: Posts: Comments:
Quoting JLPR:


yep two of the models weaken it to TD but then brings it back to TS, lets see what Henri decides
this year the storms are rebels XD


Here's a thought, the two that dissipate 10L are global models, which never developed 91L in the first place, while the statistical models showed it becoming a tropical storm.
Member Since: 24 juillet 2005 Posts: 407 Comments: 19076
108. JLPR
Quoting Weather456:


The LGEM, the one good with intensity fluctuates Henri's intensity but does not dissipate it.


yep two of the models weaken it to TD but then bring it back to TS, lets see what Henri decides
this year the storms are rebels XD
Member Since: 4 septembre 2007 Posts: 36 Comments: 5223
Quoting Weather456:


Shear better do its job, the NHC can't anymore blows.

Did I miss something is Henri doing drag... or is the nekkid swirl going to come back?
Member Since: Posts: Comments:

Viewing: 157 - 107

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14Blog Index

Top of Page

About

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

Local Weather

Clear
64 ° F
Ciel dégagé