Hawaii braces for Felicia; 99L near the Cape Verdes Islands may develop

By: Dr. Jeff Masters , 3:55 PM GMT on August 10, 2009

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A strong tropical wave (99L) is just south of the Cape Verdes Islands, 800 miles off the coast of Africa. This morning's QuikSCAT pass showed a nearly closed surface circulation, stretched out along one axis. The satellite saw winds of up to 45 mph in a band of heavy thunderstorms well south of the Cape Verdes Islands. The islands have seen winds of only 10 - 15 mph and some occasional rain showers thus far from the disturbance. Heavy thunderstorm activity associated with 99L died down this morning, but appears to be making a comeback late this morning. Wind shear is moderate, about 10 knots, and sea surface temperatures are moderately warm, about 27 - 28°C. There is a large area of dry air to 99L's north that is interfering with the storm's organization, though.


Figure 1. Current satellite image of disturbance 99L.

Wind shear is expected to be moderate, 5 - 15 knots, through Wednesday. SSTs will remain relatively constant at 27°C, but the dry, stable air of the Saharan AIr Layer (SAL) to 99L's north will be problem for it. NHC has given 99L a moderate (30 - 50% chance) of developing into a tropical depression by Wednesday morning, which is a reasonable forecast. Most of the models show some weak development, but none of them predict 99L will become a hurricane. It is too early to say if 99L will recurve north of the Lesser Antilles Islands or not, since it will be at least 5 days before the storm makes it that far. It is unusual, though, for storms forming this far north to make it all the way across the Atlantic to hit the Lesser Antilles Islands.

The GFS and ECMWF models are predicting the possible development of a new tropical wave coming off the coast of Africa late this week.

Felicia continues to weaken, but is a flash flooding threat to Hawaii
Tropical Storm Felicia has weakened steadily over the past 24 hours, thanks to cool sea surface temperatures and increasing shear. Recent satellite loops show that strong upper-level winds from the west have pushed the storm's heavy thunderstorm activity to the northeast side of the center, exposing the surface center as a swirl of low clouds. Felicia's relatively meager heavy thunderstorm activity is steadily moving away from the center of the storm.


Figure 2. History of hurricane activity over Hawaii since 1950. Hawaii islands have been hit by only 9 tropical cyclones of tropical depression or greater strength, with 4 others passing withing 75 miles of an island. Image credit: NOAA Coastal Services Center.

Sea surface temperatures (SSTs) under Felicia are 25°C, well below the 26°C threshold typically needed to sustain a hurricane. SSTs will slowly increase to 26°C by Tuesday. Wind shear has increased to a high 30 knots, and is expected to increase further to 40 knots by Tuesday. The high shear combined with the cool SSTs should continue to weaken Felicia today. I give a 30% chance that the shear will completely rip away Felicia's heavy thunderstorm activity by the time the storm reaches Hawaii, leaving only a swirl of low-level clouds that will not cause significant flooding problems. The wind speed probabilities forecast shows about a 25% chance Felicia will still be a weak tropical storm at 3 am Hawaiian time Tuesday morning, and a 15% chance the storm will have dissipated. If Felicia does hold together that long, it would be only the tenth tropical cyclone of tropical depression or higher strength to affect the islands since 1950 (Figure 2). Large swells from Felicia are already affecting the Big Island, and a high surf warning has been posted for east-facing shores of the Big Island and other Hawaiian islands. Felicia or its remnants may bring heavy rain, flash flooding, and mud slides to the islands beginning this afternoon, and a Flash Flood Watch has been posted for most of the islands.

Links to follow:
Long range radar from the Big Island
Wundermap for Hawaii

I'll have an update Tuesday morning.

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Quoting Chicklit:
(Aside: If someone posts something offensive, then reposting it and complaining about its offensiveness is just plain wacky, imho.)
What's the deal with the SE Gulf off Tampa?

shearmap
I don't know, but I am watching it out of my window haha
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2138. pottery
Hi Orca.
X man will be back tomorrow evening LOL
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2137. Asta

Been using macs since 1984- Love them too.
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2136. Patrap
Modifying a post dosent remove the original from the server.
That preview button next to the Post Comment button is there for a reason,..mostly to preview ones own post and to allow one to actually see the er,lack of logic or sense in a post.


Use it often..it may save the Local Dimension from turning in on itself too.
Member Since: July 3, 2005 Posts: 426 Comments: 128865
Quoting IKE:
Firing on all cylinders?



More like 1, haha
(Aside: If someone posts something offensive, then reposting it and complaining about its offensiveness is just plain wacky, imho.)
What's the deal with the SE Gulf off Tampa?

shearmap
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2132. gator23
Quoting Acemmett90:

the dam of kwalage lol
Quoting Patrap:
Actually,..the real District-9 in Africa is using REAL Alien Technology to Keep the SAL Pumping and the Waves a choking.

But there Leaving Weds and taking the Big Ship Home..so enjoy the Movie opening Friday and look for the tropics to Get active soon in the Basin

But you didnt hear it from me.
I was never here.

Maybe their giving their alien tech. to Bill Gates for his Hurricane Control Machine
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2131. IKE
Firing on all cylinders?

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Quoting Asta:
if you are that worried about Viruses- get a Mac - they don't get as many viruses..


I love my Mac! Never had a virus in 3 years with it.
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Quoting pottery:
Hey DDR.
Daughter was on the highway near St Augustine this afternoon in the middle of all that. Said it was Hairy.
How much rain fell on your house? Did you measure?

There was a tornado near Chaguanas yesterday too.




Your back in your own part of the world again.. or will the 'x' man be back?
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000
WTPA32 PHFO 110241
TCPCP2

BULLETIN
TROPICAL STORM FELICIA ADVISORY NUMBER 30
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP082009
500 PM HST MON AUG 10 2009

A TROPICAL STORM WATCH REMAINS IN EFFECT FOR OAHU AND FOR ALL OF
MAUI COUNTY...WHICH INCLUDES THE ISLANDS OF MAUI...KAHOOLAWE...
LANAI...AND MOLOKAI. A TROPICAL STORM WATCH MEANS THAT TROPICAL
STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA...IN THIS CASE
WITHIN THE NEXT 24 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...PLEASE MONITOR
PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST
OFFICE.

AT 500 PM HST...0300 UTC...THE CENTER OF TROPICAL STORM FELICIA
WAS LOCATED NEAR LATITUDE 20.9 NORTH...LONGITUDE 152.1 WEST...OR
ABOUT 210 MILES...EAST-NORTHEAST OF HILO HAWAII AND ABOUT 375
MILES...EAST OF HONOLULU HAWAII.

FELICIA IS MOVING TOWARD THE WEST NEAR 10 MPH AND THIS MOTION IS
EXPECTED TO CONTINUE FOR THE NEXT COUPLE OF DAYS. ON THIS TRACK...
THE CENTER OF FELICIA IS EXPECTED TO REACH THE HAWAIIAN ISLANDS ON
TUESDAY WITH RAINBANDS BEGINNING TO AFFECT THE ISLANDS OVERNIGHT.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...WITH HIGHER GUSTS.
WEAKENING IS FORECAST DURING THE NEXT COUPLE OF DAYS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 140 MILES FROM THE
CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB...29.74 INCHES.

A LARGE SWELL GENERATED BY FELICIA IS ALREADY AFFECTING THE MAIN
HAWAIIAN ISLANDS. THIS SWELL WILL CONTINUE TO BUILD ACROSS THE
STATE TONIGHT AND TUESDAY. ALSO...REGARDLESS OF THE INTENSITY OF
FELICIA WHEN IT REACHES THE HAWAIIAN ISLANDS...LOCALLY HEAVY
RAINFALL MAY OCCUR AND FLASH FLOODING REMAINS A POSSIBILITY.

...SUMMARY OF 500 PM HST INFORMATION...
LOCATION...20.9N 152.1W
MAXIMUM SUSTAINED WINDS...40 MPH
PRESENT MOVEMENT...WEST OR 270 DEGREES AT 10 MPH
MINIMUM CENTRAL PRESSURE...1007 MB

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE CENTRAL PACIFIC
HURRICANE CENTER AT 800 PM HST FOLLOWED BY THE NEXT COMPLETE
ADVISORY AT 1100 PM HST.

$$
FORECASTER BURKE/KNABB
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Quoting Asta:
if you are that worried about Viruses- get a Mac - they don't get as many viruses..
Haha. I brought that up earlier, and was bombarded with comments and complaints about macs from the pc side of the battlefield ;)
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Quoting cchsweatherman:


Been noticing that during the past few hours. Not only that, but according to the latest QuikSCAT pass, it now has a FULLY CLOSED surface circulation. May finally be getting going now, but I will wait another 12 hours before really being sold.


It's about time...
2125. Patrap

Member Since: July 3, 2005 Posts: 426 Comments: 128865
2124. pottery
Hey DDR.
Daughter was on the highway near St Augustine this afternoon in the middle of all that. Said it was Hairy.
How much rain fell on your house? Did you measure?

There was a tornado near Chaguanas yesterday too.


Member Since: Posts: Comments:
Quoting Codaflow:
Re: the virus scare-

That said, when your garden variety anti-virus software that is allowed to run in real time detects a "bad" security certificate (take note of the quotation marks around bad) it pops up a virus warning.

Not true. Outdated certs and broken cert chains of trust will NOT show up as viruses. Apples and oranges.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
2122. Asta
if you are that worried about Viruses- get a Mac - they don't get as many viruses..
now onto the tropics- what si that near the carribean.. anything??


noaa- DEVELOPMENT OF THIS SYSTEM...IF ANY...IS EXPECTED TO BE
SLOW TO OCCUR AS IT MOVES WESTWARD AT 10 TO 15 MPH. LOCALLY HEAVY
RAIN AND GUSTY WINDS SHOULD CONTINUE TO SPREAD OVER PORTIONS OF THE
WINDWARD ISLANDS THROUGH TUESDAY MORNING. THERE IS A LOW CHANCE...
LESS THAN 30 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE
DURING THE NEXT 48 HOURS."
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Quoting Acemmett90:

ok i removed it but can you two unqoute me so i dont get banned


y'all are all to be commended...shows we can police ourselves...
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2119. eye
too late already reported
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Quoting sammywammybamy:
99L new Convection Fireing near the center...



Been noticing that during the past few hours. Not only that, but according to the latest QuikSCAT pass, it now has a FULLY CLOSED surface circulation. May finally be getting going now, but I will wait another 12 hours before really being sold.
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Anti-virus is good and all but the best protection from getting one in the first place is being aware of what your clicking...

Viruses are just computer programs, and like all programs they have to be "clicked" to start, which can only be done by a human.

So don't click anything that you don't know where it goes! On the bottom of your browser if you scroll over a link it will say where it goes. Also be aware of "tiny links" those shortcut links that are short in length. That is just a re-direct and can take you to a place where you can't "see" where your going before you click it.

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Quoting Chicklit:
Evening Wunderfolk,
What does it mean when the ITCZ is higher in latitude?
...ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 16N17W 15N25W 11N29W 11N46W 9N49W 13N57W AND INTO THE SE CARIBBEAN ACROSS THE WINDWARD ISLANDS...ABC ISLANDS TO 12N71W. SCATTERED MODERATE/ISOLATED
STRONG CONVECTION IS INLAND AND WITHIN 150 NM ALONG THE COAST OF W AFRICA FROM 7N-14N. CLUSTERS OF SIMILAR CONVECTION ARE FROM 7N-11N BETWEEN 30W-39W AND FROM 7N-11N BETWEEN 49W-54W.

noaasite




Hey i was wondering where you went, as i had not seen a post by you today... : )
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2115. gator23
Quoting ALCoastGambler:
I really don't think the language is needed.

he was referring the Hoover Dam. Good Dam
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Patrap, What happened to the blob over Barbados
2113. Seastep
Quoting ALCoastGambler:
I really don't think the language is needed.


Agreed. So don't quote it.

Both can go back and edit...
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2111. eye
I third that.
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2110. 7544
looks like 99l is getting rid of its virus and is strting to gain convectiion now with a closed low dmax will be a good one if this keeps up stay tuned
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Evening Wunderfolk,
What does it mean when the ITCZ is higher in latitude?
...ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 16N17W 15N25W 11N29W 11N46W 9N49W 13N57W AND INTO THE SE CARIBBEAN ACROSS THE WINDWARD ISLANDS...ABC ISLANDS TO 12N71W. SCATTERED MODERATE/ISOLATED
STRONG CONVECTION IS INLAND AND WITHIN 150 NM ALONG THE COAST OF W AFRICA FROM 7N-14N. CLUSTERS OF SIMILAR CONVECTION ARE FROM 7N-11N BETWEEN 30W-39W AND FROM 7N-11N BETWEEN 49W-54W.

noaasite
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Quoting Acemmett90:

I really don't think the language is needed.
What happened to the weather blog? How can administration let this happened? What "the virus issues" have to do with weather? I'm a lurker here but before this was an interesting weather sight.
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2104. eye
Is 99L "firing on all cylinders" or just one?
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Quoting Stoopid1:
Oi, blogs "broke" tonight, back to lurking... will return when the ship is righted.


yup...the inmates are running the asylum...
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2102. DDR
Quoting pottery:
I notice that the shear over the Tropical Atlantic has fallen off a lot.
Water temps are pretty favourable.
Why the Fizzling of the waves?

Hey man,how are you?
Today was a mess,Rain,flood,Traffic for hours...
This is why i hate August.
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Oi, blogs "broke" tonight, back to lurking... will return when the ship is righted.
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Quoting presslord:
ROTFLMFAO!!!! Orca posted a link...wonder what part of 'virus' he doesn't understand...


Like I said earlier... if you don't know enough about computers to see where a link goes.. don't click on it. If you run your mouse over the link, you will see the URL that its pointing at.. in that case.. it was a website that sells books :)
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2098. Seastep
Quoting Codaflow:
Re: the virus scare-

Someone or some people posted content that was hosted on a military and or government site whose security certificate has either expired or was not intended for consumption by the general public for whatever mundane reason you can think ok. That said, when your garden variety anti-virus software that is allowed to run in real time detects a "bad" security certificate (take note of the quotation marks around bad) it pops up a virus warning. Your computers are safe. The only way to be 100% safe, however, is to run Firefox with the Adblock and NoScript plugins installed.

In closing, rest easy ladies and gentlemen. Your computers are safe.


Navy is on my exception list, so that does not explain it...
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2096. eye
POOF goes the magic dragon!
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2094. Patrap
Thanx Thel,..good to c yas too,..My top IT guy is on my Dell issues and well,..he has a few more failsafes to run Like you mentioned,..but some files were damaged beyond repair seems.
So,..Ill be shopping the Ol Stores for a replacement most Likely.
Member Since: July 3, 2005 Posts: 426 Comments: 128865
Quoting IKE:


You either need meds or a walk.


LOL IKE
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Quoting Patrap:


Hiya AL..a spookie night as the ol Malware virus made a appearance earlier Like it did Saturday.

I just received a message from wu-admin and there looking into the matter as we blog. They will have words on if its appropriate.
But not likely tonight.
Yeah, that's what I was saying earlier today. I got hit twice this morning and again this afternoon. My software caught it before it got into my computer though. I got lucky.
ROTFLMFAO!!!! Orca posted a link...wonder what part of 'virus' he doesn't understand...
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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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