Disturbance 98L probably no threat to land

By: Dr. Jeff Masters , 1:46 PM GMT on September 18, 2009

Share this Blog
2
+

A tropical disturbance (98L), is located midway between Africa and the Lesser Antilles Islands. This disturbance has a well-defined surface circulation, and has developed a modest amount of heavy thunderstorm activity overnight. This morning's QuikSCAT pass (Figure 1) shows a complete, circular wind pattern around the low pressure center of 98L, but top winds were only 25 mph. Wind shear is moderate, about 15 knots, and Sea Surface Temperatures are 28°C, which is about 2°C above the 26°C threshold needed to support a tropical cyclone. There is a large amount of dry air to the north and west of 98L, and this dry air is interfering with development.

The global computer models predict differing amounts of wind shear in the path of 98L as it moves west-northwest at 10 mph over the next three days. The ECMWF, GFS, and UKMET models do not develop 98L, while the NOGAPS, GFDL, and HWRF do. The models that do develop 98L predict that a strong trough of low pressure will turn 98L to the northwest and then north beginning on Monday, with the result that 98L misses the Lesser Antilles Islands by at least 500 miles. Given the moderate or higher wind shear in 98L's path, and dry air to the northwest, the system should develop only slowly. NHC is giving 98L a medium (30 - 50%) chance of developing into a tropical depression by Sunday. At this time, it does not appear that 98L will ever threaten any land areas.

The remains of Hurricane Fred are still spinning away, near 25N 66W, about 900 miles east of Florida. Wind shear is 20 knots, which is marginal for development, and there is very dry air surrounding ex-Fred on all sides. None of the computer models develop ex-Fred, and it will have a tough time regenerating with so much dry air and wind shear. The remains of Fred should move over Florida Monday night or Tuesday morning.


Figure 1. Morning QuickSCAT image of the Atlantic, showing the well-defined surface circulation of disturbance 98L. Image credit: NOAA/NESDIS.

One year anniversary of Hurricane Ike
I've been focusing this week on the 20th anniversary of Hurricane Hugo, but we also passed the one year anniversary of Hurricane Ike. Many areas along the Texas and Louisiana coast affected by Ike have fully recovered, but recovery efforts will still take many more years in other areas. In Galveston, which suffered $3.2 billion in damage, 75% of the businesses have reopened, and 95% of the population has returned. Boston.com has posted a very nice series of clickable images that show before and after scenes of some of the areas that have recovered from Hurricane Ike.

Ike washed away huge sections of beach and dunes that helped protect the Texas coast from more serious damage, and this week the state legislature approved $135 million in funds to help replace these critical natural protection systems. The restored beaches will probably last ten years, barring another strike by a hurricane of Ike's stature. Texas considers two-thirds of its 367-mile shoreline to be critically eroding, which it defines as a historical rate of more than 2 feet a year. Much of this erosion can be blamed on sea level rise. Global sea level rose seven inches over the past century, and is expected to rise at least that much over the coming century.


Figure 2. Villagers in Haiti plant one of their "Million Tree Campaign" trees. Image credit: Lambi Fund of Haiti.

Hurricane relief donations
There hasn't been a need for new hurricane-related disaster relief efforts this year, in stark contrast to 2008. However, the charities we rely on to provide disaster relief still require funds to operate in quiet years, and I encourage you to consider a donation at this time to one of my two favorite disaster relief charities. Portlight.org, which was very effective at helping out isolated, under-served communities in the wake of Hurricane Ike, is committed to raising $12,000 to purchase and outfit a mobile kitchen. This kitchen will be capable of feeding up to 2,000 people two hot meals per day in post-disaster situations. The Lambi Fund of Haiti has launched its "Million Tree Campaign", which aims to use local labor to plant a million trees over the next three years along severely deforested slopes in Haiti. Both of these charities wrote to me several times last year about the stunning generosity readers of this blog showed with their donations. Thanks!

Twenty years ago today
As Hurricane Hugo approached the U.S. Virgin Islands in the early morning hours of September 18, 1989, the storm slowed down to 10 mph. The slower speed allowed Hugo to punish the island of St. Croix with the worst beating of any location along the hurricane's destructive path. At 2am local time on September 18, 1989, Hurricane Hugo's eyewall struck St. Croix, bringing incredibly ferocious Category 4 winds, sustained at 140 mph. The hurricane's gusts were remarkably violent, and many residents witnessed tornado-like vorticies barreling across the island as the hurricane raged about them. A storm surge of 2 - 3 feet, topped by battering waves 20 - 23 feet high, assaulted the coast, adding to the destruction. Wunderground member Mike Steers wrote me to describe his experience on St. Croix: "Hugo was incredible. Many vortexes came in that night. The roar and intensity of the winds that night were incredible. When the eyewall came over, we were forced to take refuge in the bathroom as the rest of the house came apart. The pressure was so low outside the house that all of the water was sucked out of the toilet and an air draft was created through the toilet. Just when I thought it was as bad as it would get, the intensity of it all dialed up even higher. Dozens and dozens of times, my ears would violently pop due to rapid pressure changes. The next morning, of course, the devastation was unbelievable. In my front yard was a 18-foot boat with an outboard on it, that had been picked up from a marina two miles away. I had lost my house, and job, the Seaplane company I was a pilot for. After a couple months, I had to leave everything behind. In some respects, after 20 years, there an many aspects of the society that have yet to recover". Two people were killed on St. Croix, 80 injured, and 90% of the buildings were damaged or destroyed. Damage estimates for St. Croix were astronomical, over $1 billion, and the island's entire infrastructure was virtually wiped out. Six weeks after the hurricane, only 25% of the public roads had been cleared, and only 25% of the island had power.


Figure 3. GOES visible satellite image of Hurricane Hugo taken on September 18, 1989. Note the lack of cloud cover on the hurricane's southwest side, indicating that strong upper-level winds from the southwest were likely creating wind shear, weakening the storm. Image credit: Google Earth rendition of the NOAA HURSAT data base.

As Hugo departed St. Croix, strong upper-level winds from the southwest created wind shear that weakened the storm to a Category 3 hurricane with 130 mph winds. The upper level winds also caused Hugo to accelerate to 15 mph and turn more northwest. The eye passed over Puerto Rico's Vieques Island at 8am and over Fajardo on the extreme northeastern tip of Puerto Rico at 9am. On Culebra Island, an island twelve miles east of Fajardo, a gust to 170 mph was recorded by the ship Night Cap in the main harbor. The south-facing harbor received sustained southerly winds in excess of 120 mph for several hours as Hugo roared by to the south. The resulting wave "set-up" created a storm surge in excess of 13 feet in the supposedly hurricane-proof harbor. A large portion of the Caribbean's charter boat fleet, some 200 boats, was sheltering in Culebra's harbor, and 136 of these boats were badly damaged or sunk. Over 80% of the wooden structures on both Culebra and Vieques were destroyed.


Figure 4. Damage on St. Croix (two top photos), Culebra Island (bottom right), and Puerto Rico's Roosevelt Roads Navy Base (bottom left), after Hurricane Hugo. Image credit: NOAA Photo Library.

Along the northeastern coast of Puerto Rico, waves up to ten feet high riding on top of a 3 - 4 foot storm surge caused severe coastal flooding of low-lying areas. Hugo's winds tore into Puerto Rico's El Yunque rainforest, downing thousands of trees. The agricultural sector was devastated, with nearly all of the island's banana and coffee crops wiped out. Twelve deaths in Puerto Rico were attributed to Hugo, six of which occurred in the southern city of Guayama where some residents were electrocuted by downed power lines. Nearly 28,000 people were left homeless by the storm, and damage to the island exceeded $1 billion.

Storm chaser Michael Laca was at Luquillo Beach on the northeast shore of Puerto Rico, and has posted a remarkable 28-minute video on YouTube of Hurricane Hugo footage.

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: 92 - 42

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 | 33Blog Index

Quoting 19N81W:
ULL in the Central Carib seems to be dissipating....looks like it is becoming elongated on the WV Loop..what does that mean for us here in Cayman?? I have no idea...


The ULL is now near 13.5 N and 77.5 W moving just S of due W from yesterday. It still looks fairly well defined to me but will not pass through the NW Caribbean on its current track. We will likely see rain from it as the cloud cover rotates around the N side of the circulation. Hit and miss showers over the weekend.

This vorticity map shows where it is generally located at this time
Member Since: Posts: Comments:
Quoting Orcasystems:


I think its already been done... usually involves looking it your rear view mirror and seeing flashing lights :)

From the Urban Dictionary:
1. buzzkill
December 28, 2005 Urban Word of the Day
Something that spoils or ruins an otherwise enjoyable event, esp. when in relation to ruining a drunken or drug-induced high.
We were having a great time at the party until Jim puked all over the floor. That was a major buzzkill.

I was ####### off and then my dad walked in, god what a buzzkill.

2. buzzkill
Buzzkill (n. or v.trans.)
1. Buzzkill, anything that takes the edge off your fluff, a downer, something that ruins your good mood; a killjoy.
2. (verb) to selectively and deliberately bring down someone's mood by actions that are designed to irritate, annoy or downright upset a person.
Lois had a particular skill as a mother. When any of her children came home, faces beaming, eyes aglow with a report of good behavior at school, having caught a large fish or having really righteously beaten up the nerdy kid next door, she'd have just the right buzzkill to bring them back to reality. Later in life, she wondered why the kids never called, but only infrequently--she was not of an introspective nature, by and large.
Member Since: Posts: Comments:
Quoting divdog:
pleaaaaaseeee ... what are you looking at .. pictures from last week when it was a cat 3.


It's not looking real good but it is starting to look like a Marco sized depression. The center is in the convection at the moment with only the northern side of the circulation out of the convection. Personally Fred looks better than 98L to me.
Member Since: Posts: Comments:
Convection is just south of "Double 07L"s center. I expect a better looking disturbance tomorrow as it moves out of the area of 20 knot wind shear. Notice something that the NHC is now saying
"UPPER-LEVEL
WINDS ARE NOT CURRENTLY(20 knots over the disturbance) FAVORABLE FOR SIGNIFICANT(Tropical Storm) DEVELOPMENT."

I can see Fred quickly organizing into a 30-50 mph. system before landfall, my personal opinion. The NHC is hinting that very slow development is possible, just not significant.
Member Since: July 1, 2008 Posts: 13 Comments: 7340
Quoting presslord:


Thanks! Hope my comment wasn't a...ah...buzzkill...


LOL...EVERYBODY MAMBO!
Member Since: Posts: Comments:
Quoting Floodman:


From buzzkill to porn monger...IKE, you have many talents


Ahhh post of the day! ROFL.
Member Since: Posts: Comments:
Quoting caneluver:
convection is moving over the center of Fred. Looking real good at the moment.
pleaaaaaseeee ... what are you looking at .. pictures from last week when it was a cat 3.
Member Since: Posts: Comments:
Quoting mikatnight:


I suppose you're right. I find myself agreeing with you more often than not, but Haiti's history has got to be the most disillusioning of any other country in this hemisphere. Reckon I’ll be sticking to US charities for now (assuming I had a spare penny to give to anyone – right now it’s all we can do to keep afloat).


Thanks! Hope my comment wasn't a...ah...buzzkill...
Member Since: Posts: Comments:
Quoting IKE:
Fred looks like a naked swirl w/a goatee.


LOL I see it.
Member Since: Posts: Comments:
Quoting Floodman:


The day is young...let these folks get some coffee in them and we'll be off to the races; on the other hand, it may be a while as most of them are still in school...LOL


Ring the warning bell when they arrive so I can leave lol
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
Surprised I haven't seen more "98L is a fish" comments lol


The day is young...let these folks get some coffee in them and we'll be off to the races; on the other hand, it may be a while as most of them are still in school...LOL
Member Since: Posts: Comments:
Good morning Dr. Masters! Thanks once again for a thorough update!!

Looks like "FredEx" needs a shave everyone!! Hopefully that PESKY thing just runs out its course as an intermittent area of convection! We need no surprises!! Hopefully the "Saga of FredEx" ends late Sunday, maybe it'll give SC some much needed rain!!

Well, last night, while we were bickering amongst ourselves about the ULL and "FredEx", 98L popped up!! SUPRISE!!! Hopefully, over the course of its life, it'll BEHAVE itself and NOT bother any land mass! Although some in the Caribbean Island chain said they can use some rain!!

This 2009 Atlantic Tropical Season has been highlighted by some of the most unpredictable storms, except for Bill, which pretty much followed the computer models, like a well behaved system!! Ana, the on again/off again convective burst; Claudette the lil' GOM surprise which behaved well, Danny and Erika which annoyed everyone to no end; last but not least "FredEx", which defied all the models, as far as direction, but peacefully entertained bloggers on WU to no end!!

Peace to all, happy blogging, hoping for a well behaved balance of the "WEIRD" 2009 Atlantic season :0)
Member Since: Posts: Comments:
ULL in the Central Carib seems to be dissipating....looks like it is becoming elongated on the WV Loop..what does that mean for us here in Cayman?? I have no idea...
Member Since: Posts: Comments:
Quoting reedzone:
You can see "Double 07L" is trying to make another comeback but I think it won't come back till it reaches the Bahamas where the lower shear is. It's currently getting sheared in 20 knots. "Double 07L" should move out of the shear later on today or tonight. I think this is why models have started running (again) for it, because conditions could and look to become favorable tomorrow and before landfall. If it stays weak, it should make landfall in South/Central Florida. If it strengthens before landfall, a northwesterly turn will occur and North Florida through the Carolinas should watch it.

"Double 07L"

i see a naked swirl with a goatee like IKE said. This system is toast as far as tropical development. Maybe a little rain to somebody.
Member Since: Posts: Comments:
Quoting StormW:
Here we go again with dual vorticies:

98L RGB LOOP


Good morning.

What I find interesting is the 12.6 N position given for the center of 98L on the WU Home page. I doubt that position is correct given the Quikscat pass from earlier and when you look at the loops it seems evident that 13.3 is where the best rotation center is seen. There is also a small blow up of convection there supporting that position.
Member Since: Posts: Comments:
Surprised I haven't seen more "98L is a fish" comments lol
Member Since: Posts: Comments:
Quoting Orcasystems:


ROFL, I think we already figured that one out :)


I'm trying tyo figure how many ways I can fit it into a sentence, you know "Buzzkill is as buzzkill does, my momma used to say"
Member Since: Posts: Comments:
Quoting presslord:


before you judge them harshly, you oughta check out their website...Lambi Fund is a very cool organization....


I suppose you're right. I find myself agreeing with you more often than not, but Haiti's history has got to be the most disillusioning of any other country in this hemisphere. Reckon I’ll be sticking to US charities for now (assuming I had a spare penny to give to anyone – right now it’s all we can do to keep afloat).
Member Since: Posts: Comments:
Quoting Floodman:


By the way, Flood's secret word of the day is "buzzkill"


ROFL, I think we already figured that one out :)
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting IKE:
Fred looks like a naked swirl w/a goatee.


From buzzkill to porn monger...IKE, you have many talents
Member Since: Posts: Comments:
Quoting Orcasystems:


I think its already been done... usually involves looking it your rear view mirror and seeing flashing lights :)


Well, that would certainly be a buzzkill as most of us in here can attest...you don't have to be a cop to be a buzzkill, though, huh?

By the way, Flood's secret word of the day is "buzzkill"
Member Since: Posts: Comments:
Quoting JLPR:
you guys did noticed that Fred's LLC is incomplete, right? =P



Now you've done it...hey, wait a minute, you were a buzzkill just then...see? That's cool!
Member Since: Posts: Comments:
Quoting mikatnight:
Thanks Doc. I gotta wonder about any Haiti charity. What's to stop the idiot government down there from just cutting 'em all down again? The difference between them and the Dominican Republic is stark. Haiti is the epitome of the "crabs in a barrel" (sociological) analogy...


before you judge them harshly, you oughta check out their website...Lambi Fund is a very cool organization....
Member Since: Posts: Comments:
Quoting Grothar:


I know there are annular storm, but are there tubular storms as well. Fred looks like a floating "tube" at the moment?
That shape is only occurring because of the large amount of northerly shear blowing the thunderstorms off of the circulation. The circulation itself is actually very "round"
Member Since: Posts: Comments:
Thanks Dr. Masters for the update. The only chance that 98L has of making it to the CONUS to make landfall is if he does what Fred has done.
Member Since: Posts: Comments:
Quoting Floodman:


You forgot buzzkill...hey, is there a place I can go to learn that? buzzkill, I mean...seems as though there's a market for that


I think its already been done... usually involves looking it your rear view mirror and seeing flashing lights :)
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting IKE:


I'm a downcaster.

I use to be a disc-jockey....loved doing it, but no money.

I've been in sales since Labor Day 1984.

Been married a few times...have a kid 30...and a grandchild.

There's my life history...now...back to the weather.


You forgot buzzkill...hey, is there a place I can go to learn that? buzzkill, I mean...seems as though there's a market for that
Member Since: Posts: Comments:
Quoting watcher123:
50:

The same could be said for Washington.


I don't believe Haiti in any way compares with the United States of America. We are the chosen people; the "City on the Hill". We are responsible for the betterment of mankind. Haiti is the antithesis.
Member Since: Posts: Comments:
Quoting weathermanwannabe:


Been noticing that too; still brining me rain in the FL Big Bend and training showers when it should have lifted out by now.....I wanted to go fishing this weekend and the weather is looking iffy right now cause of the stalled low.. :)

Might want to stand down on fishing, just too squally. Lots of fooball on anyway.
Member Since: Posts: Comments:
59. IKE
Fred looks like a naked swirl w/a goatee.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting mobilegirl81:
The NWS is easing by the fact that they busted the forecast on the low pressure over ARK/LA/MS. That thing was supposed to lift to the northeast 2 days ago and be gone.


Been noticing that too; still brining me rain in the FL Big Bend and training showers when it should have lifted out by now.....I wanted to go fishing this weekend and the weather is looking iffy right now cause of the stalled low.. :)
Member Since: Posts: Comments:
Quoting TampaSpin:

Areas of Interest with a little makings a smaller version of the Perfect Storm#2 in the Tropical Update!


My mother is in the whole prophecy bit and said she heard that 3 or 4 storms would merge together into a Katrina-like storm and hit central Florida. I would not loose sleep over it, but those are some interesting tracks if some development takes place.
Member Since: Posts: Comments:
You can see "Double 07L" is trying to make another comeback but I think it won't come back till it reaches the Bahamas where the lower shear is. It's currently getting sheared in 20 knots. "Double 07L" should move out of the shear later on today or tonight. I think this is why models have started running (again) for it, because conditions could and look to become favorable tomorrow and before landfall. If it stays weak, it should make landfall in South/Central Florida. If it strengthens before landfall, a northwesterly turn will occur and North Florida through the Carolinas should watch it.

"Double 07L"

Member Since: July 1, 2008 Posts: 13 Comments: 7340
55. JLPR
Quoting tornadofan:


Don't try to confuse us with facts. :)

very well then =P
Member Since: Posts: Comments:
Quoting JLPR:
you guys did noticed that Fred's LLC is incomplete, right? =P



Don't try to confuse us with facts. :)
Member Since: Posts: Comments:
Blog Update
Reflector site for those at work, includes Dr. Masters & Weather456, daily update.


AOI

AOI

AOI

AOI
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting jeffs713:

The government isn't cutting them down. The people are cutting them down for firewood, because the government in Haiti is generally corrupt and inept, and won't support their people.


Yeah, like I said - crabs in a barrel. No foresight, no cooperation, anyone who takes power on the premise of reform quickly turns into that which they replaced. It’s like Woody Allen’s “Bananas” down there…
Member Since: Posts: Comments:
The NWS is easing by the fact that they busted the forecast on the low pressure over ARK/LA/MS. That thing was supposed to lift to the northeast 2 days ago and be gone.
Member Since: Posts: Comments:
Nice burst of convection just to the SE of the center of "Dead Fred"!
Member Since: Posts: Comments:


I know there are annular storm, but are there tubular storms as well. Fred looks like a floating "tube" at the moment?
Member Since: Posts: Comments:
Quoting JLPR:


and with that map you posted you can see 98Ls anticlone reformed to the west close to 40 so 98L could end up with favorable wind shear soon


Yes, 98L will be interesting. I remember seeing models curve Frances before it missed the trough and headed west towards the USA. So out to sea is likely, but things can change.
Member Since: July 1, 2008 Posts: 13 Comments: 7340
43. JLPR
you guys did noticed that Fred's LLC is incomplete, right? =P

Member Since: Posts: Comments:
Curious to what effect the the trough that will be digging into the middle of the country next week will have on the remnants of fred
Member Since: Posts: Comments:

Viewing: 92 - 42

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 | 33Blog 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

Overcast
67 °F
Overcast