Tropical Storm Helene arrives; 94L a potential threat to the Lesser Antilles

By: Dr. Jeff Masters , 10:41 PM GMT on August 17, 2012

After a long path across the Atlantic that mirrored the track of Hurricane Ernesto, Tropical Depression Seven finally got its act together enough over the Bay of Campeche tropical storm breeding grounds to earn the name Helene. Helene's formation on August 17 ties 2012 with 1933 for the 2nd earliest appearance of the Atlantic's eighth tropical storm. Only 2005 had an earlier formation date of the season's eighth storm. Most of this year's storms have been weak, though, so the total Accumulated Cyclone Energy (ACE) of 21 is not that much higher than the normal year-to-date ACE of 15, based on a 1981 - 2010 ACE climatology. The normal yearly ACE for the Atlantic is 104. Helene doesn't have much room to work with before landfall, but has the potential to be a prodigious rainmaker for Mexico, with NHC predicting 5 - 10 inches for portions of Northeast Mexico. This part of the coast is not in drought, so will be prone to heavy flooding. Fortunately, Ernesto's main rains fell to the south of where Helene's rains are falling. Helene's rains should remain south of Texas, though we can't rule out a few thunderstorms bringing 1 - 2 inches of rain to extreme South Texas on Saturday and Sunday.


Figure 1. Afternoon satellite image of Helene.

94L a potential threat to the Lesser Antilles
A large tropical wave emerged from the coast of Africa Thursday night, and was designated Invest 94L by NHC this Friday morning. The models have been impressed this system, and develop it into a tropical storm by the middle of next week. The latest set of 12Z (8 am EDT) model runs are divided on how far west 94L will make it before curving more to the northwest. The ECMWF model keeps 94L weak for the next 5 - 6 days, and has progressively been bringing the storm closer to the Lesser Antilles Islands with each successive run. The ECMWF predicts 94L will pass very close to the northern Lesser Antilles August 24 - 25 as a weak tropical storm. The 12Z GFS model predicted recurvature of 94L well to the east of the Lesser Antilles and Bermuda, but the latest 18Z run has the storm plowing through the Lesser Antilles on Thursday, August 23, as a strong tropical storm, then becoming a hurricane in the Eastern Caribbean. Given that our two top models for forecasting hurricane tracks are increasingly showing a threat to the Lesser Antilles, residents of the islands should pay close attention to the progress of 94L. The eventual track of 94L will depend on the strength of the storm over the next seven days, which is difficult to forecast, since 94L will have the usual trouble with dry air to the north from the Saharan Air Layer (SAL.) With the models changing their tune drastically from run to run, its tough to say what land areas might be most at risk from the storm in the long term. In their 2 pm EDT Tropical Weather Outlook, NHC gave 94L a 10% chance of developing into a tropical depression by Sunday afternoon.


Figure 2. MODIS satellite image of Invest 94L taken at 8 am EDT August 17, 2012, off the coast of Africa. Image credit: NASA.

Jeff Masters


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

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

Viewing: 426 - 376

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36Blog Index

Quoting popartpete:
I know it's going to be said sooner or later: Will 94L go through Herbert's Box?

There is no such thing as Herbert's Box.
And Hebert's boxes are imaginary.
goodnight! Sorry to call Helene poof but good grief.
She's barely hanging on.
Member Since: Posts: Comments:
wash115, I am already preparing for anything that whatever this system may bring to PR if it comes to the Eastern Caribbean. I went today to a hardware store and bought panels,flashlights,candles and a power plant. I am avoiding the big rush when watches and warnings are issued.
Member Since: December 31, 1969 Posts: Comments:
I'm sorry, RedWagon. It's been a brutal 12 months for you.
Member Since: Posts: Comments:
I know it's going to be said sooner or later: Will 94L go through Herbert's Box?
Member Since: Posts: Comments:
i wish i had $5000 for evere time some one said fish storm on this blog
Member Since: Posts: Comments:
Quoting sunlinepr:
Freaking serious....




that would be a HUGE storm...

Member Since: Posts: Comments:
Quoting Chicklit:
Hunger sharpens the senses.. those of us about to lose to the life-or-death drought we're in and can't get out of naturally have to nitpick even small storms for possible rain.
Member Since: December 31, 1969 Posts: Comments:
Its moving "North", Its "OnShore", its moving "NNE", Wow!!!! Go with what the experts say. Period!
Member Since: Posts: Comments:
Quoting Chicklit:
I will concede on the Dvorak and Funktop loops there is still some spin over water.
LinkFunk Top Loop

The center is probably at 97W 22.6N or thereabouts.


Very foolish of me to think I know anything without checking the data.


22.6N 97.0w seem corect to me

Member Since: Posts: Comments:
Quoting gustavcane:

Hello KoritheMan, I have been reading your post for a long time here. I think we both live in the same state. so I hope you are right about it being a little early for a sharp northeastward turn to occur from the Bay of Campeche. if you are wrong it may be very bad for us here next week.


Either way, we would not be talking about a major hurricane if it decided to move this way, as the GFS suggests a little bit of westerly shear. Also, recall last year how Nate was supposed to impact the northern Gulf Coast from a similar location but failed to do so. And that was three weeks later.
Member Since: Posts: Comments:
Quoting JLPR2:


Really doubt 94L will see the Gulf, it should recurve before that, the question here is, where will it finally recurve? :P


well just going by what the GFS is thinking

but its too early to say yes or no so as I said I'll wait till it reaches near 40W
Member Since: Posts: Comments:
414. JLPR2
Oh well, hoping for a track shift with the 00z GFS.
*fingers crossed*
Member Since: Posts: Comments:
413. JLPR2
Quoting washingtonian115:
If that pans out Parts of PR could get strong winds ans surge.


Yes, beach erosion would be problem too. And the DR would get the brunt of it. :\
Member Since: Posts: Comments:
I will concede on the Dvorak and Funktop loops there is still some spin over water.
LinkFunk Top Loop




Very foolish of me to think I know anything without checking the data.
Helene @8 p.m.
REPEAT...CENTER LOCATED NEAR 20.6N 96.1W AT 17/2130Z
AT 17/1800Z CENTER WAS LOCATED NEAR 20.3N 95.9W

Member Since: Posts: Comments:
411. JLPR2
Quoting wunderkidcayman:
the thing that I find is that GFS keeps on shifting further south that 94L could soon be a Caribbean GOM curving to Fl type storm and I don't like it


Really doubt 94L will see the Gulf, it should recurve before that, the question here is, where will it finally recurve? :P
Member Since: Posts: Comments:
410. NJ2S
Wow just my luck looks like the worst case scenario for me hearing to PR on the 27 and back to NYC on the 1st :(
Member Since: Posts: Comments:
Quoting RTSplayer:
Two members like NOLA, so we got an "upgrade" from the previous run where just one member did that...

wow so now they tryna bring two ensembles towards me. smh! i think this is texas storm they need the rain
Member Since: Posts: Comments:
Quoting JLPR2:


Not exactly, it passes really close to PR on its way WNW/NW towards DR/Mona Passage, we wouldn't get a direct hit, but considering it is expected to be a big system effects on PR with this track wouldn't exactly be light.

If that pans out Parts of PR could get strong winds and surge.
Member Since: December 31, 1969 Posts: Comments:
I repeat it hasn't made landfall...not even close probably something else.
Member Since: Posts: Comments:
406. JLPR2
Quoting sunlinepr:


Look at the GFS new path... passing S into RD....


Not exactly, it passes really close to PR on its way WNW/NW towards DR/Mona Passage, we wouldn't get a direct hit, but considering it is expected to be a big system effects on PR with this track wouldn't exactly be light, especially in Western side of the island.

Member Since: Posts: Comments:
Quoting Hurricanes101:


actually they did go home, but I think that was planned lol



ture lol
Member Since: Posts: Comments:
the thing that I find is that GFS keeps on shifting further south that 94L could soon be a Caribbean GOM curving to Fl type storm and I don't like it
Member Since: Posts: Comments:
Quoting KoritheMan:


Climatologically, it's still a little early for a sharp northeastward turn to occur from the Bay of Campeche.

Hello KoritheMan, I have been reading your post for a long time here. I think we both live in the same state. so I hope you are right about it being a little early for a sharp northeastward turn to occur from the Bay of Campeche. if you are wrong it may be very bad for us here next week.
Member Since: Posts: Comments:
Quoting mitthbevnuruodo:
Geeesh, I go to work and come home to find, we got Helene and already made landfall it seems while I was out pah LOL Wasn't even a TD again when I left!

Awww, Hernesto not on the map anymore, was so used to seeing him there LOL

Well, Washingtonian might get a might Isaac afterall?!?!

No landfall
Member Since: Posts: Comments:
Wonder if this works

Member Since: December 31, 1969 Posts: Comments:
400. JLPR2
Quoting washingtonian115:
Really hope you all don't get a storm.We'll see how the pattern evolves though.Make sure you take heed from your officials before what anyone says on this blog..


Don't worry, I'm pretty good at keeping myself and my family informed.
Member Since: Posts: Comments:
399. JLPR2
Quoting Tropicsweatherpr:


At least Ada said about watching it without getting into more details.


And that's why she is the better meteorologist. XD

One never says never when it comes to the weather.
Member Since: Posts: Comments:
Quoting Tazmanian:



right why would the recon be out there still if the storm made land fall they would all ready be heading home


actually they did go home, but I think that was planned lol
Member Since: Posts: Comments:
to be fair, the recon ended 2 hours ago...but it didnt look a whole lot better on satellite then either. patience, people. recon is the best instrument we have, obviously, so you need to filter other data through it, not filter it through the other data...

Quoting Tazmanian:



right why would the recon be out there still if the storm made land fall they would all ready be heading home
Member Since: Posts: Comments:
Quoting GTcooliebai:
Great point and reminder. Although some folks on this blog have been through Major Hurricanes and can at least offer some advice in case you are worried.
Advice is good.Just don't take it to heart though is all I'm saying.
Member Since: December 31, 1969 Posts: Comments:
Geeesh, I go to work and come home to find, we got Helene and already made landfall it seems while I was out pah LOL Wasn't even a TD again when I left!

Awww, Hernesto not on the map anymore, was so used to seeing him there LOL

Well, Washingtonian might get a might Isaac afterall?!?!
Member Since: Posts: Comments:
Quoting WxGeekVA:


Best analogue I can find for pre- Isaac. David 1979. I think it will recurve a little east of there though, so shift the track north of Hispaniola about 100 miles east.

That would be fatal for Haiti and DR.
Member Since: Posts: Comments:
Quoting washingtonian115:
Really hope you all don't get a storm.We'll see how the pattern evolves though.Make sure you take heed from your officials before what anyone says on this blog..
Great point and reminder. Although some folks on this blog have been through Major Hurricanes and can at least offer some advice in case you are worried.
Member Since: Posts: Comments:
Quoting WxGeekVA:


Best analogue I can find for pre- Isaac. David 1979. I think it will recurve a little east of there though, so shift the track north of Hispaniola about 100 miles east.

Man!
How light of heart you make things?
If you get an action replay of that then you better be looking for Climatic Asylum.
Member Since: Posts: Comments:
Quoting Gearsts:
And Ada?


At least Ada said about watching it without getting into more details.
Member Since: December 31, 1969 Posts: Comments:
Quoting evilpenguinshan:
Everybody calm down, we're approaching DMin, of course she looks bad. But the NHC didnt say she was moving N/NNE for no reason...you guys can serve me crow (preferably deep fried) tomorrow morning if she doesn't show some convection near the LLC come DMax tomorrow XD

Agree.What became of Helene practically vanished yesterday night..only to wake up to a well organized tropical system.I'm sure if she's not over land by tomorrow morning she will have a better day.
Member Since: December 31, 1969 Posts: Comments:
Quoting Hurricanes101:
and now we get 1 person after another saying the system is moving onshore when recon obs and satellite LOOPS clearly show the circulation over water



right why would the recon be out there still if the storm made land fall they would all ready be heading home
Member Since: Posts: Comments:
Quoting gustavcane:
Hello everyone.I have been a member here reading everyone's posts and lurking here for a long time. I have been a member here since at least 2002.Last time I posted here was in 2008 when Hurricane Gustav was about to hit my area. Now I think it is time to start posting with you guys here again. Look like Tropical Storm Helene is starting to feel that strong Trough and Ridge to the north and is starting to pull her like a magnet to the NNE. what do you guys think.

It's definitely moving north. I wouldn't quite say northeast yet though. It may move that way in a few days as the trough over the East deepens.
Member Since: Posts: Comments:
Quoting redwagon:

The Texans that don't need it are, and the rain will start evaporating in about 45mins once it reaches the hot, dry Hill Country. Our 'soil' is shiny white limestone which reflects light and creates its own damned High pressure dome.

dang...
Member Since: Posts: Comments:
Quoting redwagon:

The Texans that don't need it are, and the rain will start evaporating in about 45mins once it reaches the hot, dry Hill Country. Our 'soil' is shiny white limestone which reflects light and creates its own damned High pressure dome.


It does?
Member Since: Posts: Comments:
Quoting gustavcane:
Hello everyone.I have been a member here reading everyone's posts and lurking here for a long time. I have been a member here since at least 2002.Last time I posted here was in 2007 when Hurricane Gustav was about to hit my area. Now I think it is time to start posting with you guys here again. Look like Tropical Storm Helene is starting to feel that strong Trough and Ridge to the north and is starting to pull her like a magnet to the NNE. what do you guys think.


Climatologically, it's still a little early for a sharp northeastward turn to occur from the Bay of Campeche.
Member Since: Posts: Comments:
Quoting RTSplayer:


I'm aware of what recon claims, but there's just nothing whatsoever in the satellite presentation to suggest the storm is anything other than a decoupled piece of remnant garbage.

Regardless of where the CoC is, it's obvious all the convection and mid level circulation wen west to WSW a long time ago...


Recon doesn't claim anything, it is the most accurate piece of info we have out there

again the satellite loops show a circulation over water and nothing even to hint one over land
Member Since: Posts: Comments:
Mexican Radar

Click on "Altimira" and animate it.

Not only has it made landfall, it's moving SW at a decent clip, and you can see the rotation clearly.
Member Since: December 31, 1969 Posts: Comments:
Everybody calm down, we're approaching DMin, of course she looks bad. But the NHC didnt say she was moving N/NNE for no reason...you guys can serve me crow (preferably deep fried) tomorrow morning if she doesn't show some convection near the LLC come DMax tomorrow XD

Quoting RTSplayer:


I'm aware of what recon claims, but there's just nothing whatsoever in the satellite presentation to suggest the storm is anything other than a decoupled piece of remnant garbage.

Regardless of where the CoC is, it's obvious all the convection and mid level circulation wen west to WSW a long time ago...
Member Since: Posts: Comments:
Quoting gustavcane:
Hello everyone.I have been a member here reading everyone's posts and lurking here for a long time. I have been a member here since at least 2002.Last time I posted here was in 2007 when Hurricane Gustav was about to hit my area. Now I think it is time to start posting with you guys here again. Look like Tropical Storm Helene is starting to feel that strong Trough and Ridge to the north and is starting to pull her like a magnet to the NNE. what do you guys think.

Gustav was in 08
Member Since: Posts: Comments:
Quoting Chicklit:
Looks like Texas is getting some rain!

The Texans that don't need it are, and the rain will start evaporating in about 45mins once it reaches the hot, dry Hill Country. Our 'soil' is shiny white limestone which reflects light and creates its own damned High pressure dome.
Member Since: December 31, 1969 Posts: Comments:
Quoting JLPR2:


Haha, yeah and I wouldn't expect it to come back for awhile.
Ah... the suffering! XD
Really hope you all don't get a storm.We'll see how the pattern evolves though.Make sure you take heed from your officials before what anyone says on this blog..
Member Since: December 31, 1969 Posts: Comments:
Quoting Tropicsweatherpr:


By the way,today yes Deborah did it again. She said there is nothing to worrie about.
And Ada?
Member Since: Posts: Comments:
Helene @8 p.m.
REPEAT...CENTER LOCATED NEAR 20.6N 96.1W AT 17/2130Z
AT 17/1800Z CENTER WAS LOCATED NEAR 20.3N 95.9W

FORECAST VALID 18/0600Z 21.1N 96.9W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 20NE 40SE 40SW 20NW.

FORECAST VALID 18/1800Z 22.1N 98.1W...INLAND
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 30NE 30SE 0SW 20NW.

FORECAST VALID 19/0600Z 22.9N 99.0W...INLAND
MAX WIND 30 KT...GUSTS 40 KT.

FORECAST VALID 19/1800Z 23.5N 99.5W...POST-TROP/REMNT LOW
MAX WIND 25 KT...GUSTS 35 KT.

FORECAST VALID 20/1800Z...DISSIPATED

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 20.6N 96.1W

Member Since: Posts: Comments:
Hello everyone.I have been a member here reading everyone's posts and lurking here for a long time. I have been a member here since at least 2002.Last time I posted here was in 2008 when Hurricane Gustav was about to hit my area. Now I think it is time to start posting with you guys here again. Look like Tropical Storm Helene is starting to feel that strong Trough and Ridge to the north and is starting to pull her like a magnet to the NNE. what do you guys think.
Member Since: Posts: Comments:

Viewing: 426 - 376

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36Blog Index

Top of Page

Category 6™

About

Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather