Isaac approaching hurricane strength

By: Angela Fritz , 9:14 PM GMT on August 27, 2012

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Isaac is walking the line of hurricane status this afternoon after a hurricane hunter mission investigated the storm and found winds of 80+ mph with the SFMR instrument, which looks down at the surface from the plane and estimates what wind speeds are. This instrument has a notoriously rough time in doing so when there's heavy rain, and since the strongest winds were recorded coinciding with the strongest rain, you can imagine that this region of high wind speed could be suspect. The hurricane hunter mission is still in the storm, so I imagine they will issue a special update if needed. Currently the best estimate of wind speed within the storm is 70 mph. Isaac's pressure has been dropping today as well and is now 981 mb. Isaac is moving northwest at 12 mph--no change since this morning. Satellite loops show that Isaac remains large, though asymmetric, with most of the strong thunderstorm activity on the west and southwest side. Isaac's southeast side continues to struggle with dry air and wind shear, which could help to moderate Isaac's intensity as it approaches the coast.

An oil platform in the northern Gulf of Mexico is reporting sustained winds from the north-northeast at 40 mph this afternoon. A buoy west of Tampa, Florida is recording sustained winds around 30 mph, and platforms south of Louisiana are recording winds from 35-40 mph. The widespread heavy rain of yesterday has lightened up in Florida, but a strong line of thunderstorms in one of Isaac's outer bands is training northward along and offshore of the east coast of Florida, affecting everyone from Miami to Jacksonville.

This afternoon the AP reported that Isaac's death toll in Haiti jumped to 19, which puts Isaac's total death count at 21. It appears most of the deaths in Haiti were due to collapsing structures.


Figure 1. Satellite imagery of Tropical Storm Isaac around 3pm EDT on Monday.

Track forecast:
Models seem to be coming into better agreement today on where Isaac will make landfall, closing in on Louisiana and New Orleans as most likely landfall point. The ECMWF, HWRF, and UKMET all suggest New Orleans as the landfall location. The GFS is only slightly west of that. The GFDL is the farthest west, predicting landfall near the Louisiana-Texas border. Landfall timing remains Tuesday night. Beyond landfall, Isaac is expected to move north toward the Midwest through the rest of this week, however, models are showing that the system will likely slow down around landfall time, prolonging impacts like surge and inland flooding.

Intensity forecast:
The closer Isaac gets to landfall without having formed an eye, the better it is for intensity at landfall. Isaac has strengthened only modestly in the past 24 hours, and is still struggling with a less-than-conducive atmospheric environment. The HWRF remains on the high end of the intensity spectrum, suggesting Isaac will be a weak category 2 upon landfall. Other models suggest it will be a strong category 1, but the difference is splitting hairs. The National Hurricane Center's official forecast is for Isaac to continue strengthening over the next day, reaching category 2 at landfall.


Figure 2. Tide gauge data from St. Petersburg, Florida. The green line shows the storm surge. As Isaac's counterclockwise winds blew offshore this morning, water levels feel two feet at St. Petersburg. The winds switched to onshore this afternoon as the center of Isaac moved more to the northwest, bringing a storm surge of two feet to the city.

Storm surge observations from Isaac
This morning, as Isaac's counter-clockwise winds brought offshore winds to the Tampa/St. Petersburg area, ocean waters fell two feet along the coast. This afternoon, winds have shifted to blow onshore, and a two foot storm surge has been observed at Naples, Fort Meyers, and St. Petersburg on the west coast of Florida. Water levels have also begun to rise along the coast of Louisiana, with a storm surge of 1.5 feet already occurring at Shell Beach on the east side of New Orleans in Lake Borgne.

Angela and Jeff

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1654. will40
Quoting Orcasystems:
OMG... everyone is coming back... where is Floodman??


he was on last nite
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1653. Scotth
Quoting Stormbugn:
t

I believe he was joking and BECAUSE of his illiteracy we lose the intent behind his attempt at sarcasm. However, he tries which is more than many of us "lurkers" do. I have only recently started posting. I also mentor mentally challenged people. I do not feel that we have the right to ask them to permabann him. If someone explains to him how offensive that post was, I am sure he would apologize for it. I live in MS close to the coast and expect major damage and flooding. But I don't hold his words against him. Some will because they find him annoying but it seems this blog is his life.


You are correct sir...I have been here since 2004 and he was here before ME! This IS his life. Its really all he has and those that are upset with him need to grow up and move on.
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Quoting Beachfoxx:
Who'd thought we would be "lurkers"? LOL
Lots of years and lots of storms and here we are - still together after all these years.
Hey, is there a song in there??? LOL


It seems like good common sence about watching these storms has gone out the window>
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1651. MrsOsa
Quoting DFWjc:
I love how XTRP has the storm coming all the way over to the DFW area in Texas....SMH



The XTRP is not a forecast model. It simply shows where the storm would go if it stayed going in exactly the same direction that it is now.
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Quoting nola70119:


Pascagoula is in Mississippi....
are you sure if TWC has anything to do with it they will have it in CA.... I mean Mobile Bay was in MS earlyer today from what TWC said.... LOL

Taco :o)
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dear doctor jeff do know thunderstorm outflowbandary
duryline thunderstorm severe threat of floods torndos
and quter hill size
thank you eric booth forecaster
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Quoting DFWjc:
I love how XTRP has the storm coming all the way over to the DFW area in Texas....SMH



Give it time, the XTRP will shift east sooner or later.
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OMG... everyone is coming back... where is Floodman??
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Quoting moonlightcowboy:


Pretty sure I know that. Might check a map and see what's east of Pascagoula. ;P No worries. Really appreciated your commentary and especially the rainfall chart earlier. Thanks.


Sure, just confused, if you had said takes Alabama out of the picture I would have understood. So you think that Morgan City is not possible based on that map? Just curious why?
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1644. DFWjc
Quoting caneloader:
Well even if Isaac totally craters and turns out to be a big nothingburger, it's been a big test for New Orleans. First "Katrina" scare since the levees were fixed... was proud to see the local news and how the buses were ready, the pumps were tested, the floodgates were ready to shut...

Not only have a lot of old memories been dredged up, but it looks like maybe even we stubborn, happy-go-lucky Cajuns have a leasrning curve.

Great warm-up.


How much deeper are the Levees now? Are the gates to block more water coming into the Lake?
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1643. jake436
Quoting Caner:
dare i ask what Taz said to earn the wrath of the blog gestapo?

Must be far back, went back 4 pages and found nothing but whining about it ;]
Basically (paraphrasing), he said "this thing better be a CAT 3 when I wake up or I'm dropping a cow on the NHC". Typical Taz being overdramatized by a bunch of people that have been on here a week.
Member Since: August 31, 2006 Posts: 0 Comments: 271
Data from a couple of rigs near the path of Isaac.
Link

Link
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1641. will40
Quoting IcemanMC:
Glad to see some oldies taking up for one old members; Patrap missing all the fun with Isaac



yes i bet he is upset about it also
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Who'd thought we would be "lurkers"? LOL
Lots of years and lots of storms and here we are - still together after all these years.
Hey, is there a song in there??? LOL
Quoting cjnew:
Hiya Foxx!
I think everyone is still around, we've just done it so long we sit back and observe. haha
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Quoting Beachfoxx:
LOL - good to see everyone!

Nothing like a Cane to bring us all out of the wood work!


there are some nice waves washing up on the beach of that little bar right now... small enough for SM to surf on :)
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Quoting mobilebayal:
Taz was my first friend when I joined Wu in 07. He is the blog mascot.
Hey Mobilebay :o) I'm back :o)
looks like MS maybe back in the Mix again :o(

Taco :o)
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1637. DFWjc
I love how XTRP has the storm coming all the way over to the DFW area in Texas....SMH
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GFS running.
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It's fun watching all the wishcasting at play. Carry on.

(logging in just to prove I'm still around), but mostly I read instead of post anymore.
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are all the storms this year going to be like this???
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Quoting cjnew:
Hiya Foxx!
I think everyone is still around, we've just done it so long we sit back and observe. haha


Well said! ;)
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Glad to see some oldies taking up for one old members; Patrap missing all the fun with Isaac
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1631. will40
Quoting JeffM:


Remember the whole Lefty's wave and StormTop nailing Katrina? Cannot believe it's been 7 YEARS!



yes Jeff that was a time for sure
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Well even if Isaac totally craters and turns out to be a big nothingburger, it's been a big test for New Orleans. First "Katrina" scare since the levees were fixed... was proud to see the local news and how the buses were ready, the pumps were tested, the floodgates were ready to shut...

Not only have a lot of old memories been dredged up, but it looks like maybe even we stubborn, happy-go-lucky Cajuns have a leasrning curve.

Great warm-up.
Member Since: Posts: Comments:
Quoting dogsgomoo:
Just put him on ignore if he's that annoying to you. It really does make things smoother all around. Despite the fact that he makes interesting observations I've had him on ignore a few times in the past. I suspect people do at some point or other.

I have a hard time parsing what he writes and when he posts a lot, goes off on a tangent or does the whole "blog cop" shtick .... But like someone mentioned he has his moments of contribution and insight.

At first I assumed his communication style was due to a learning or physical disability until someone mentioned that it's due to English not being his native language. It could be all three for all I know but his intent doesn't seem to be to hurt anyone and the weather seems to be his life.
English isn't the first language for many people here ,including me. For obvious reason ,storms cross many areas and nations with different languages and backgrounds. For me as mainly a lurker here, I like Taz, and even with my difficulties in the English language like to read what he have to say and learn from what he post... here.
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1628. will40
Quoting AllyBama:
Will, I saw that - lol...seems like there are more of us "old-timers" around here lately - which is a good thing. BTW, I still got my Emerald Isle web cam site handy!



yeaaaaaaaaaaaa good girl we almost lost it last year with Irene
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1627. Caner
dare i ask what Taz said to earn the wrath of the blog gestapo?

Must be far back, went back 4 pages and found nothing but whining about it ;]
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1626. cjnew
Hiya Foxx!
I think everyone is still around, we've just done it so long we sit back and observe. haha
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Quoting nola70119:


Pascagoula is in Mississippi....


Pretty sure I know that. Might check a map and see what's east of Pascagoula. ;P No worries. Really appreciated your commentary and especially the rainfall chart earlier. Thanks.
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Quoting fldude99:


I'm out. I'm sorry, but when someone wishcasts a cat 3 heading for the Big Easy, 7 years after Katrina, he/she gets no wiggle room from me


Drop it or leave.. your choice.
To many people like Taz... its a dangerous little icon to pick on.
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1623. will40
Quoting moonlightcowboy:


Only if you start dancing! ;)

No, you're still gonna get wind, rain! STAY DILIGENT! :) 1/2 the time (or better) I don't know what the hell I'm talking about! ;P


ut ro we need to get Ally a pole
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LOL - good to see everyone!

Nothing like a Cane to bring us all out of the wood work!
Quoting will40:



yea SJ was on here the other nite looking Lefty lol
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1621. JeffM
Quoting will40:



yea SJ was on here the other nite looking Lefty lol


Remember the whole Lefty's wave and StormTop nailing Katrina? Cannot believe it's been 7 YEARS!
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Will, I saw that - lol...seems like there are more of us "old-timers" around here lately - which is a good thing. BTW, I still got my Emerald Isle web cam site handy!
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Quoting AllyBama:


does this mean that I can relax now?..lol


Only if you start dancing! ;)

No, you're still gonna get wind, rain! STAY DILIGENT! :) 1/2 the time (or better) I don't know what the hell I'm talking about! ;P
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Quoting Beachfoxx:
Chill out - he is a good soul. Let him be!


I'm out. I'm sorry, but when someone wishcasts a cat 3 heading for the Big Easy, 7 years after Katrina, he/she gets no wiggle room from me
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Quoting moonlightcowboy:
The stars are starting to line up now for Isaac, getting that neast wall closed off the the dry air. Shouldn't be long now. IMO, this takes anything west of NOLA and anything east of Pascagoula out of the picture towards landfall. So, MS, you are likely it, A G A I N!

WATER VAPOR LOOP


Pascagoula is in Mississippi....
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Taz was my first friend when I joined Wu in 07. He is the blog mascot.
Member Since: August 17, 2007 Posts: 0 Comments: 1098
1615. will40
Quoting Beachfoxx:
Wow - The old gang and the Troops rally! Hi CJ, good to see you!



yea SJ was on here the other nite looking Lefty lol
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Quoting moonlightcowboy:
The stars are starting to line up now for Isaac, getting that neast wall closed off the the dry air. Shouldn't be long now. IMO, this takes anything west of NOLA and anything east of Pascagoula out of the picture towards landfall. So, MS, you are likely it, A G A I N!

WATER VAPOR LOOP


does this mean that I can relax now?..lol
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1613. JeffM
Quoting moonlightcowboy:
The stars are starting to line up now for Isaac, getting that neast wall closed off the the dry air. Shouldn't be long now. IMO, this takes anything west of NOLA and anything east of Pascagoula out of the picture towards landfall. So, MS, you are it!

WATER VAPOR LOOP


Sounds like what happened last night with folks clamoring about people waking up to a well-developed cane. This thing just cannot get over the hump and it's been that way throughout its entire existence.
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Quoting CloudGatherer:


Ah, I understand now. Just not used to thinking of cyclones as wayward children. Although it's not a terrible way to anthropomorphize Isaac. Just hoping he doesn't throw a tantrum when he gets to shore.


I hate it when you guys write stuff like that.. I have to cut and paste it into google :(

Even then... I have NFI what it means.

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Wow - The old gang and the Troops rally! Hi CJ, good to see you!
Quoting cjnew:


Don't mess with the Taz.
:D
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Quoting Joanie38:
Good Evening..Central LA here. We are prepared...prepare for the worst and hope for the best...All loose objects brought inside, got non-perishable foods,dog food, LOTS of water, batteries, flashlights, etc...I guess you CAN SAY....WE are ready!!!! :)



Always good to be prepared. I remember when "Edouard" was supposed to be a cat 1 coming at us in the Houston area. I think it only sprinkled that day lol. However, my grandpa bought a generator just in case. Weeks later Ike hit. You never know! Be safe!
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1609. will40
Quoting Beachfoxx:
Will - long time no see!


Hiya Beachy
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Quoting CloudGatherer:


Ah, I understand now. Just not used to thinking of cyclones as wayward children. Although it's not a terrible way to anthropomorphize Isaac. Just hoping he doesn't throw a tantrum when he gets to shore.


I realized after I posted that..that you , the op, might not get my dry sense of humor...lol...sorry for the confusion
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The stars are starting to line up now for Isaac, getting that neast wall closed off from the dry air. Shouldn't be long now. IMO, this takes anything west of NOLA and anything east of Pascagoula out of the picture towards landfall. So, MS, you are likely it, A G A I N!

WATER VAPOR LOOP
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1606. cjnew
Quoting Orcasystems:


Ditto... what she said :)


Don't mess with the Taz.
:D
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Will - long time no see!
Quoting will40:


!!!!! ALLY!!!!!!
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1604. dader
Does anyone know how to decipher Joe Bastardi's "power scale" for cyclones? This guy is a complete lunkhead- no wonder he only appears on Fox Business News.
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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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