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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Quoting 19N81W:
2009, Caribbean and US...am I wrong? did we have something named make landfall this year? wow if we did what a storm it must have been!...


Ana and Erika went through the Leewards

Claudette made landfall on the Gulf coast of Florida

and the remnants of Fred was the main caused the 2009 Georgian floods
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting GeoffreyWPB:
How The Earth Was Made...on the History Channel....talking about the Loch Ness Monster. Wasn't that famous picture already proved a fraud?
No, (Nessie) was killed in a extra-tropical cyclone in the early 1950,s. It was unable to come up for air do to heavy wave action....:)
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No recon planned as of now.
Member Since: September 10, 2007 Posts: 0 Comments: 11278
Are the Recon flying to Henri?
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Quoting Weather456:


See if this link works


That link does work. Thanks :)
Let me see if I can also view archives on my blog as well.
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2009, Caribbean and US...am I wrong? did we have something named make landfall this year? wow if we did what a storm it must have been!...
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How The Earth Was Made...on the History Channel....talking about the Loch Ness Monster. Wasn't that famous picture already proved a fraud?
Member Since: September 10, 2007 Posts: 0 Comments: 11278
Quoting NCHurricane2009:
Evening all,

I see we have Henri (seemed to organize fast!) and what's left of Grace has moved into the British Isles.

I've got a couple of technical difficulties here. When I tried to make a post on my blog, I get "ERROR: It appears this user does not have a Wunderblog." Same error when I try to view my blog archives, and strangely the same error I get when I look at Weather456's blog archives. Otherwise, I can view everyone else's blog. Any help would be great.

Thanks


See if this link works
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Evening all,

I see we have Henri (seemed to organize fast!) and what's left of Grace has moved into the British Isles.

I've got a couple of technical difficulties here. When I tried to make a post on my blog, I get "ERROR: It appears this user does not have a Wunderblog." Same error when I try to view my blog archives, and strangely the same error I get when I look at Weather456's blog archives. Otherwise, I can view everyone else's blog. Any help would be great.

Thanks
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Sorry, he said carib too, so add Erika.
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Quoting Seastep:


He said CONUS hit.


Yea I did see all of that, so then pick out the ones for that region, I included all that affected some land.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Hopefully this season will see enough activity to keep all the fools from moving back to the gulf coast that sensibly moved away after the 2004 storms. Doing work here in Tampa this past summer was been a very enlightening experience for me in how ill prepared the population is. I did not think it would be anywhere near so bad. Driving along I-275 past downtown Tampa and the residential areas I gaze over are very similar in construction and quality to the poor areas of New Orleans. Flimsy metal roofs, the majority of the buildings in low areas, old construction that clearly has seen no renovation in decades... the area is definitely due. If there are building codes here, no structure is recent enough to have seen enforcement. A mere TS would relocate Ybor City to north of the interstate.

The worst thing about all of this? When a storm finally does roll into the GOM and wash over the city, all of these people are going to go crying to the government for aid. Brilliant. It must be a wonderful to completely ignore common sense and move a coastal city in a hurricane prone area. I stopped for morning coffee and picked up the local free paper to check on events in the area last week and what was on the front page but a complaint that the governor wants to allow the insurance companies to raise rates.

ALLOW? They actually put caps on insurance rate increases here? What lunatics live in an area where they shouldn't even be allowed to build in the first place and cry when insurance companies have to raise rates to cover these poor fools who couldn't plan ahead?

These quiet seasons without any storms to scare away the retirees... the false sense of security people are lulled into is a bad thing for all of us.
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TROPICAL STORM HENRI HAS DEVELOPED AT 06/2100 UTC...NEAR 17.8N 54.0W...OR ABOUT 600 MILES/965 KM TO THE EAST OF THE NORTHERN LEEWARD ISLANDS. HENRI IS MOVING TOWARD THE WEST-NORTHWEST 16 KT. THE CENTER OF HENRI AND THE ASSOCIATED STRONG WINDS ARE EXPECTED TO REMAIN WELL TO THE NORTH OF THE LESSER ANTILLES. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 35 KT WITH GUSTS TO 45 KT. HENRI IS EXPECTED TO BE A SHORT-LIVED TROPICAL CYCLONE AND COULD WEAKEN TO A REMNANT LOW BY WEDNESDAY NIGHT.

Call me a wishcaster but it just doesn't seem right that nothing develops.
Member Since: July 11, 2006 Posts: 14 Comments: 11355
293. jipmg
Quoting CaribBoy:
I have to say Henry is moving more WEST than WEST-NORTH-WEST


I think its moving North west, based on visible loop
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Quoting Weather456:


Claudette only?

Try Ana, Bill, Danny, Erika and Fred, not to mentioned Grace is heading for Ireland.


He specified US/Carribean
Member Since: September 23, 2005 Posts: 14 Comments: 11215
Quoting Weather456:


Claudette only?

Try Ana, Bill, Danny, Erika and Fred, not to mentioned Grace is heading for Ireland.


He said CONUS hit.
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Quoting Chicklit:
Ike seemed to have a chip on his shoulder that nothing was forming, I noticed that, if this helps. Anyway, what's going on with Henri? I've been working like a fiend, came on the blog, and found a named system from something that looked embryonic yesterday. What's going on? And where's JLPR? He's usually here. So tell me. I'm really dying to know and will have to soon turn in since my deadlines are all at ground zero and I barely have a moment to stop.


Quick and dirty.

Naked swirl. 30% chance. 2 hrs later convection fires over center. TS Henri.

Still lots of shear. Still watching sat and saying "How in the heck is it holding that convection under 20-30kts of shear?"

Check in tomorrow.
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I have to say Henry is moving more WEST than WEST-NORTH-WEST
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Quoting Seastep:


LOL. Pay up. I think I took it.

Tropical Storm Claudette 08/16-08/17


Claudette only?

Try Ana, Bill, Danny, Erika and Fred, not to mentioned Grace is heading for England.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting 19N81W:
I did make a bet back in I think June/July saying no named storms would make landfall in the US or Caribbean...how do you check post history?? I think a couple guys took the bet...obviously its not going to happen as the active period seems to be ending....anyone want to pay up??


You realize that Claudette did hit Florida, right?
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Quoting 19N81W:
I did make a bet back in I think June/July saying no named storms would make landfall in the US or Caribbean...how do you check post history?? I think a couple guys took the bet...obviously its not going to happen as the active period seems to be ending....anyone want to pay up??


LOL. Pay up. I think I took it.

Tropical Storm Claudette 08/16-08/17
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Quoting 19N81W:
I did make a bet back in I think June/July saying no named storms would make landfall in the US or Caribbean...how do you check post history?? I think a couple guys took the bet...obviously its not going to happen as the active period seems to be ending....anyone want to pay up??


You mean 2009?
Member Since: July 24, 2005 Posts: 407 Comments: 19076
284. jipmg
big ball of convection trying to hold onto the eastern side of the center.. I guess the center is right under that western tip of the convection based on visible loop
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283. JLPR
Quoting Chicklit:
Ike seemed to have a chip on his shoulder that nothing was forming, I noticed that, if this helps. Anyway, what's going on with Henri? I've been working like a fiend, came on the blog, and found a named system from something that looked embryonic yesterday. What's going on? And where's JLPR? He's usually here. So tell me. I'm really dying to know and will have to soon turn in since my deadlines are all at ground zero and I barely have a moment to stop.


Im here but im doing college homework, projects , etc. :|
Member Since: September 4, 2007 Posts: 36 Comments: 5223
I did make a bet back in I think June/July saying no named storms would make landfall in the US or Caribbean...how do you check post history?? I think a couple guys took the bet...obviously its not going to happen as the active period seems to be ending....anyone want to pay up??
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280. JRRP
.
Member Since: August 16, 2007 Posts: 0 Comments: 5984
I wonder if the direction of the shear has something to do with it ... I know shear is less of an impact when storms move with the shear direction. I have to think that its a gradual shift from being worst a storm moving directly into shear versus a storm moving with it ... since the strong winds arent out of due west, perhaps it's not as detrimental as the same amount of sheargoing directly against the movement as we've seen time and again this year..Another thing ... strong easterlies in the lower levels seemed to prohibit the LLC from closing off by going against any western motion component of the LLC. Weirdly enough once westerly shear crept in the LLC was able to close off, possibly counteracting the effects of the lower easterlies ... lose your top to finish your bottom .. weird little TCs this year * note this is all just rambling and conversation .. take it with a grain of salt*
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Ike seemed to have a chip on his shoulder that nothing was forming, I noticed that, if this helps. Anyway, what's going on with Henri? I've been working like a fiend, came on the blog, and found a named system from something that looked embryonic yesterday. What's going on? And where's JLPR? He's usually here. So tell me. I'm really dying to know and will have to soon turn in since my deadlines are all at ground zero and I barely have a moment to stop.
Member Since: July 11, 2006 Posts: 14 Comments: 11355
We adore atmo, btw...he just pulls for the wrong team...
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Everyone is welcome to stop by and leave a comment...except atmo...who, as you will see, has abused the privlege...


Link
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The track for SHIPS basically lifts Henri northward around 65W.

AL 10 2009100700 03 SHIP 0 181N 547W
AL 10 2009100700 03 SHIP 12 195N 573W
AL 10 2009100700 03 SHIP 24 208N 598W
AL 10 2009100700 03 SHIP 36 217N 621W
AL 10 2009100700 03 SHIP 48 229N 642W
AL 10 2009100700 03 SHIP 60 240N 657W
AL 10 2009100700 03 SHIP 72 251N 670W
AL 10 2009100700 03 SHIP 84 264N 677W
AL 10 2009100700 03 SHIP 96 276N 679W
Member Since: September 23, 2005 Posts: 14 Comments: 11215

Strange when a named storm in the Atlantic feels like a good thing, but it's been such an inactive season, Henri feels normal!
Member Since: July 11, 2006 Posts: 14 Comments: 11355
Quoting GeoffreyWPB:
Taz...you remark about a post you did not like...then you quote it. Doesn't make sense. Just report it...or ignore him...and problem solved.



true but am wanting too no why he was so rude this AM
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so guys where is it COC

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 07 OCT 2009 Time : 001500 UTC
Lat : 18:04:39 N Lon : 54:41:15 W


CI# /Pressure/ Vmax
2.7 /1003.0mb/ 39.0kt


Final T# Adj T# Raw T#
(3hr avg)
2.7 2.9 3.3

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : +13.5C Cloud Region Temp : -24.2C

Scene Type : SHEAR (0.08^ TO DG)

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : ATLANTIC

Tno/CI Rules : Constraint Limits : 0.2T/hour
Weakening Flag : OFF
Rapid Dissipation Flag : OFF


06/2345 UTC 17.9N 54.4W T1.5/1.5 HENRI -- Atlantic

AL, 10, 2009100700, , BEST, 0, 181N, 547W, 35, 1007, TS, 34, NEQ, 60, 0, 0, 0, 1012, 150, 45, 0, 0, L, 0, , 0, 0, HENRI, M,


200910061800 17.7 -53.4 35


5:00 PM AST Tue Oct 6
Location: 17.8°N 54.0°W
Max sustained: 40 mph
Moving: WNW at 18 mph
Min pressure: 1007 mb
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Taz...you remark about a post you did not like...then you quote it. Doesn't make sense. Just report it...or ignore him...and problem solved.
Member Since: September 10, 2007 Posts: 0 Comments: 11278
2009 has been the season of the weird, who knows, and fortunate, considering what Bill could have done had that storm made landfall.

ShearMap
Member Since: July 11, 2006 Posts: 14 Comments: 11355
Convections really blowing up on Henri. I hope nature isn't developing shear proof hurricanes. I'm reminded of that line..."Nature finds a way."
It's certainly found a way to confound the experts and not a few of amateurs this season. I agree this has been anything but boring. :)
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Quoting WeatherStudent:
G'evening, all! Who in here thinks that Henri's forecast track during the upcoming 11pm advisory will be longer and reach out more then westward then the 5pm advisory did?

hi guys I think they might time will tell
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I didn't think any models predicted more than 20-25 knots shear, the same shear it developed under.
Member Since: August 10, 2007 Posts: 0 Comments: 3278
Quoting WeatherStudent:
G'evening, all! Who in here thinks that Henri's forecast track during the upcoming 11pm advisory will be longer and reach out more then westward then the 5pm advisory did?


The center presented in the atcf at 0000 UTC is along the lines of the NHC forecast track so it might not change much. Intensity however, I only agree up to 3 days, I still think the upper environment will improve beyond then so I have not change by views that I'm not 100% buying dissipation.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Quoting Weather456:


I did not had QS in 1998 and I did not know to use it until 2001, we have to go back to old fashion forecasting. It might be a bit more difficult but ASCAT has a narrower swath and the same time lapse as QS, which is a downgrade. Tonight is a perfect example. We were able to get a center without using QS and it verified per the 0000UTC, so this is what we might be in for, so start learning (not in a rude way though).


Well... that's the beauty of Meteorology... just when you think you got it... you really don't because there's a new "variable" that causes you to rethink your original strategy and start learning/developing new techniques to be better next time... always a learning en devour.
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Quoting WeatherStudent:
G'evening, all! Who in here thinks that Henri's forecast track during the upcoming 11pm advisory will be longer and reach out more then westward then the 5pm advisory did?


At this point... NOTHING would surprise me.
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Quoting ElConando:


It could miss Haiti, which would definitly boost its chances.


That is a Hurricane grave yard... So if Henri wants to visit the area, no problem.

NOTE: Since people here take things the wrong way... I'm not wishing/wanting any death and destruction to Hispaniola.
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Quoting BahaHurican:
Wow! I have had internet access problems since Friday, and looks what happens! 2 new storms!!!


You missed one heck of a weekend. I mean seriously.
Member Since: July 24, 2005 Posts: 407 Comments: 19076

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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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