Isaac pounding Louisiana, Mississippi, Alabama, and Florida

By: Dr. Jeff Masters , 4:01 PM GMT on August 29, 2012

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Hurricane Isaac continues to lumber slowly northwestwards at 6 mph, as it pounds Louisiana, Mississippi, Alabama, and Florida's Panhandle with torrential rains, high winds, and a damaging storm surge. The eye was partially over water for most of the 15 hours after Isaac's official landfall at 7:45 pm EDT Tuesday night, but New Orleans radar shows the eye of the storm is now fully ashore near Houma. The radar echoes show some weakening on the west side of the eyewall, where dry air has infiltrated the storm. Wind shear remains light, and upper level outflow over Isaac is as impressive as we've seen so far, with a strong outflow channel to the north, and a respectable one to the south, as well. Infrared and visible satellite loops show a very large, symmetric, and well organized storm, and Isaac is going to be able to stay near Category 1 hurricane strength all day today. This will allow Isaac to drop rainfall amounts of 15 - 20" in some areas of Louisiana before the storm is over. A few rainfall totals from Isaac through 11 am EDT:

9.26" New Orleans Lakefront Airport
5.59" Belle Chasse, LA
5.21" Mobile, AL
3.65" Hattiesburg, MS
3.42" Gulfport, MS
2.81" Biloxi, MS


Figure 1. Morning radar reflectivity image from New Orleans.

A dangerous storm surge event underway
Isaac is bringing a large and dangerous storm surge to the coast from Central Louisiana to the Panhandle of Florida. Late this morning was high tide along much of the coast, and the highest water levels of Isaac are likely being experienced at many locations. At 11:30 am EDT, here were some of the storm surge values being recorded at NOAA tide gauges:

8.0' Waveland, MS
8.2' Shell Beach, LA
2.0' Pensacola, FL
4.6' Pascagoula, MS
3.4' Mobile, AL

The peak 11.06' storm surge at 1:30 am EDT this morning at Shell Beach, which is in Lake Borgne, 20 miles southeast of New Orleans, exceeded the 9.5' surge recorded there during Category 2 Hurricane Gustav of 2008. In general, the storm surge heights from Isaac have been more characteristic of a strong Category 2 hurricane, rather than the weak Category 1 hurricane one might suppose Isaac is, based on its top sustained winds of 75 - 80 mph. The Saffir-Simpson Scale for ranking hurricanes is only a crude measure of their potential impacts.

A storm surge estimated at 12' moved up the Mississippi in Plaquemines Parish near Port Sulphur, LA, near 8:30 pm EDT Tuesday, causing overtopping of the levees and flooding of homes in the mandatory evacuation areas behind the levees. These levees were not part of the $14.5 billion levee upgrade New Orleans got after Hurricane Katrina, and were not rated to Category 3 hurricane strength, like the levees protecting New Orleans are. The surge continued upriver, elevating the water levels 10' in New Orleans (103 miles upstream from the mouth of the Mississippi), 8' in Baton Rouge (228 miles upstream), and 1.4' at Knox Landing, an amazing 314 miles upstream. The river was 7' low due to the great 2012 U.S. drought, and I suspect the near-record low flow rate of the river allowed the storm surge to propagate so far upstream. The salt water from the storm surge will be slow to leave the river, due to the continued winds of Isaac keeping the surge going, plus the very low flow rates of the river. One benefit of the heavy rains of 10 - 20 inches expected to fall over Louisiana over the next two days will be to increase the flow rate of the Mississippi River, helping flush the salt water out of the river. The low flow rates of the Mississippi had allowed salt water to move upriver to just south of New Orleans over the past few weeks, threatening the drinking water supply of Plaquemines Parish.


Figure 2. Tide gauge data from Waveland, Mississippi. The green line shows the storm surge. The red line is the storm tide, the height of the water above Mean Sea Level (MSL.) The storm tide at Waveland currently (9') is 2' higher than that of Category 2 Hurricane Gustav of 2008. Image credit: NOAA Tides and Currents.

Tropical Storm Kirk in the Central Atlantic
Tropical Storm Kirk formed Tuesday night in the Central Atlantic. Kirk's formation at 03 UTC on August 29 puts 2012 in 4th place for earliest formation date of the season's 11th storm. Only 2005, 1995, and 1933 had an earlier formation date of the season's 11th storm. Kirk should stay well out to sea and not trouble any land areas.


Figure 3. Morning satellite image of Tropical Storm Kirk.

Invest 98L in the Eastern Atlantic
A tropical wave (Invest 98L) is about 750 miles west-southwest of the Cape Verde Islands, and is moving west to west-northwest at about 15 mph. In their 8 am EDT Tropical Weather Outlook, NHC gave 98L a 50% chance of developing by Friday morning. Several of the models develop 98L into a tropical depression by this weekend, but none of the reliable models foresee that 98L will be a threat to the Lesser Antilles. The storm may be a threat to Bermuda next week, but it is too early to say if it may threaten the U.S.

Jeff Masters

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Nightime (just after midnight yesterday morning) image of moonlit Isaac approaching Lousiana, from NASA's Suomi-NPP weather satellite. Click for larger image and story:

NASA


Technology: plus 1,000. Awesomeness: plus 1,000,000.
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Quoting JasonRE:


What do you mean? How wont' it make it to Lafayette?


Storm looks to be heading more north now.... some breezes but thats about it. Not much rain either.
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Quoting CajunCrawfishhunter:
I thinking the Storm may not make it to Lafayette

That's a nice thought, but we'll be getting it later today into the evening. Hopefully the winds will begin to decrease.
Member Since: September 5, 2007 Posts: 0 Comments: 3488
(click to enlarge)
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142. A4Guy
Quoting oceanspringsMS:


Actually that is Hwy 90 and casino row on the beach. Downtown is just North by a block and has a little higher elevation.


Was just in Ocean Springs, too. LOVE it ther e- great littly artsy downtown area.
How are y'all doing? Is the bayfront submerged?
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Back when it was still moving across the Keys, didn't a few of the forecast models have Isaac just 'hanging out' for a day or so on the coast before moving on? It seemed inconceivable to almost everyone on the blog at the time.

Prayers to those covering the storm and to the emergency personnel tasked to deal with it.
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Quoting CajunCrawfishhunter:
I thinking the Storm may not make it to Lafayette


What do you mean? How wont' it make it to Lafayette?
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Quoting Unfriendly:


plaquemines... not plague mines. 2nd time you said that.
I imagine they are feeling plagued about now. Our prayers are with them.
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138. A4Guy
Quoting LargoFl:
downtown Biloxi....................


How did you get that pic of Biloxi by the Beau Rivage casino? I was just there last week - would like to see if there are other webcams or bloggers there posting images.
Thanks!
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Quoting LargoFl:
from Plaguemines parish..................


I guess someone didnt tell him that Isaac was coming..
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Isaac dumped over 16" of rain on Wellington, FL - 12 miles inland from West Palm Beach, FL Sunday - Tuesday. Flooding there continues to make many roads impassable for 3-4 days now as the storm sewers are not allowing water to drain - because where they are draining/pumping into - canals - are also heavily flooded. This breaks the recent rain record for Wellington from a single hurricane set by Irene 12 years ago. May be the most rain from a single tropical storm there in 50 - 100 years.
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Quoting TomballTXPride:


Looks like his eye has closed up again.
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Quoting CybrTeddy:


We're more than aware of the situation with Isaac, we all have been following it very closely and we are aware of how bad it is in Louisiana right now, but there are other systems out there to track. I've been watching and posting on Isaac BUT I have also been posting and tracking 98L and Kirk as tropical cyclone genesis simply fascinates me.


we also have people outside the US that these systems could affect..as I said before, there are those of us who can multitask..
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Isaac running at 973 pressure at noon. Category 1.?????
This is one Freaky storm !

So sorry to see/hear of the hardship and losses.
Cant seem to find any sympathy for the ones that stayed put and are in trouble though. Tough !
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Quoting LAlurker:
Really, fellow bloggers, I know that many of you are tired of Isaac after 2 weeks of postings, but this is still going on here in LA, a lot still happening, still classed as a Cat 1 by NHC. Can you please refrain from posting about invests and TDs that won't affect anyone for days, weeks, or never. Give Isaac another day or two. Thanks!

Doc mentioned it in his post so it iss on topic. its tropical weather so its on topic. no reason why not...
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Quoting Unfriendly:


plaquemines... not plague mines. 2nd time you said that.
ok you go web surf and post..im tired lol
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Quoting KEEPEROFTHEGATE:




Collapsing?? That looks like it's maintaining it's strength.. Structure has improved despite it being over land.
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Quoting LargoFl:
Rainfall totals from NWS/New Orleans:
Audubon Park: 12.67"
Lakefront Airport: 9.03"
by Dan Holiday - The Storm Report 12:45 PM

Looks like radar is severely underestimating rainfall totals, which is a common occurrence with tropical cyclones.

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Quoting LargoFl:
Rainfall totals from NWS/New Orleans:
Audubon Park: 12.67"
Lakefront Airport: 9.03"
by Dan Holiday - The Storm Report 12:45 PM


Wow. And they've probably got a lot more coming.
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I hope everyone here takes note as those that ignored the authorities and chose to stay despite the warnings, are now showing all of us what can and does happen in these storms. Nobody can tell ahead exactly what will happen when a storm like this strikes. This is a very good education for all of us living in a hurricane zone!
I feel badly for all of them, and hope the loss of life is minimal. Stay strong LA!!!
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A Category 1 hurricane, Isaac came ashore near the mouth of the Mississippi River, drenching a sparsely populated neck of land that stretches into the Gulf of Mexico.

According to Bay News 9 Meteorologist Juli Marquez, the storm's slow movement will continue to dump heavy rains on Louisiana.

As Isaac neared the city, there was little fear or panic. With New Orleans' airport closed, tourists retreated to hotels and most denizens of a coastline that has witnessed countless hurricanes decided to ride out the storm.

"Because of the slow movement, there may be anywhere from seven to 20 inches of rain," Marquez said. "The heavy rainfall amounts in Louisiana and Mississippi may lead to some flooding."

Isaac also promised to test a New Orleans levee system bolstered after the catastrophic failures during Hurricane Katrina. However, in a city that has already weathered Hurricane Gustav in 2008, calm prevailed.

President Barack Obama is promising FEMA's resources to Florida and the other Gulf Coast states after Gov. Rick Scott declared a statewide state of emergency.
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Quoting LargoFl:
from Plaguemines parish..................


plaquemines... not plague mines. 2nd time you said that.
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Quoting GeorgiaStormz:
Interesting spiraling patern in the eye:

Looks like it going to NOLA. The wall is very close
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Quoting LargoFl:
from the 10 am NHC.............SINCE ISAAC IS FORECAST TO MOVE SLOWLY OVER THE NEXT 24-36 HOURS...

THERE WILL BE A PROLONGED THREAT OF FLOODING FROM HEAVY RAINS OVER
THE NORTHERN GULF COAST AREA AND THE SOUTH-CENTRAL UNITED STATES.

NATIONAL OCEAN SERVICE TIDE GAGES INDICATE THAT STORM SURGE HEIGHTS
OF 6 TO 8 FEET ARE STILL OCCURRING ALONG PORTIONS OF THE COAST OF
SOUTHEASTERN LOUISIANA AND MISSISSIPPI. GIVEN THE LONG DURATION
OF ONSHORE FLOW IN THESE AREAS...WATER LEVELS ARE EXPECTED TO REMAIN
HIGH THROUGH TODAY.

A SPECIAL THANKS TO THE CREWS OF THE AIR FORCE RESERVE AND NOAA
HURRICANE HUNTERS WHO FLEW A TOTAL OF 34 HAZARDOUS MISSIONS INTO
ISAAC...WHICH RESULTED IN AN IMPRESSIVE TOTAL OF 95 CENTER FIXES.

FORECAST POSITIONS AND MAX WINDS

INIT 2
9/1500Z 29.6N 90.7W 65 KT 75 MPH...INLAND
12H 30/0000Z 30.2N 91.4W 55 KT 65 MPH...INLAND
24H 30/1200Z 31.2N 92.2W 45 KT 50 MPH...INLAND
36H 31/0000Z 32.8N 93.1W 30 KT 35 MPH...INLAND
48H 31/1200Z 34.6N 93.5W 25 KT 30 MPH...INLAND
72H 01/1200Z 38.0N 92.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 02/1200Z 40.0N 89.0W 15 KT 15 MPH...POST-TROP/REMNT LOW
120H 03/1200Z 41.0N 85.0W 15 KT 15 MPH...POST-TROP/REMNT LOW

$$
FORECASTER STEWART
I must say I have to tip my hat off to those guys.
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Saw someone asked about a weather report from Hattiesburg. So far, so good here when it comes to severity of wind. Rain has been coming down since last night and we've had near 4 inches. Now that Isaac is jogging north a bit, the heaviest rains with the stronger winds are getting closer. We'll have to see what happens. I haven't heard of any damage here yet. Highest gusts have been around 40mph.
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Quoting LargoFl:
yes the poster said it was by the casino's


The Grand
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75 rescued from flooded homes and rooftops in Plaquemines Parish, CNN affiliate WWL reports
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Quoting Autistic2:


Does that include staying when your told to leave?


That's just plain dumb.
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Rainfall totals from NWS/New Orleans:
Audubon Park: 12.67"
Lakefront Airport: 9.03"
by Dan Holiday - The Storm Report 12:45 PM
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I thinking the Storm may not make it to Lafayette
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After watching Isaac for the last week I'm so thankful that K.W. was barely affected and very concerned for those in the thick of it now. This is a very intriguing storm indeed. The double landfall from space was Out of this World..literally.
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one poster reports.........Strongest Wind Speeds:
South Marsh Island - 69 mph
Burns Point - 60 mph
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I don't think it's fair to call anyone heartless for having a larger perspective on the situation. These people committed a selfish act after they were told that their homes will be inundated, their lives will be in danger and that rescue would be difficult. Through their shortsightedness they are draining the resources of emergency personnel away from those in danger through no fault of their own and making an already enormous task that much more difficult. You or I or any of the posters here would have the heart to reach out to such people in our own lives if faced with a similar situation and try to dissuade them from choosing their willful self-interest over their neighbor's desire to keep them from harm's way. My heart goes out to those rescuers who are forced to save these people who passed up the chance to save themselves.
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Quoting LargoFl:
downtown Biloxi....................


Actually that is Hwy 90 and casino row on the beach. Downtown is just North by a block and has a little higher elevation.
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Quoting GeorgiaStormz:
Interesting spiraling patern in the eye:


Looking at the radar loop of the eye and such I would imagine that Slidell LA is getting POUNDED.
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Quoting MahFL:
oh oh, smaller eye has formed.


It's collapsing, losing structure.
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Quoting USCGLT:

Looks like the Beau Rivage Casino?
yes the poster said it was by the casino's
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I posted this yesterday, and will post it again from time-to-time as people start the recovery process.

Some comments and suggestions to smooth and demystify the insurance claim process:

Make sure your agent has your current phone number(s). When you call in your claim, either to your agent or to a claim center number, designate which of your phone numbers should be primary so that your adjuster doesn't have to play "telephone tag".

If you have both wind and flood damage, you likely (but not always) will end up with two different adjusters.

If you were paid for damage from Gustav (for example), and did not get around to fixing it, don't claim it again. Insurance fraud is almost always a felony, and adjusters have access to the photos taken after the last storm you experienced.

Try not to throw anything away until the adjuster has done his/her inspection. If you MUST throw stuff away (food spoilage, for instance) document it with photos and receipts.

Personal property loss inventories should be completed before the adjuster arrives. Receipts are very helpful, especially with big-ticket items. Include model and serial numbers. If you are claiming damage to electronics/appliances due to lightning strike, get an electrician's affidavit to submit to your adjuster.

It is a myth that adjusters will try to "lowball" a claim. You will likely be working with an independent adjuster who gets paid on a fee schedule (the higher the estimate, the bigger the adjuster's fee). That being said, the experience level of adjusters varies tremendously. Have a list of all known damage ready for the adjuster's arrival, discuss the list (or do a quick walk-around), and then let the adjuster work without interruptions.

A "scope" of damage should be agreed with the adjuster before he/she leaves. It is common for hidden problems to appear as repairs are being made; these are typically addressed in the form of supplemental claims ("supplements"). Do not expect the adjuster to, for instance, open walls and ceilings to check for damp insulation.

Start "mitigating" (preventing further) damage as soon as possible (this is a requirement stated in your policy). Examples: Tarping a roof that is now missing shingles, drying carpets. Legitimate mitigation expenses should be documented with photos and receipts, and the adjuster will add these expenses to the estimate.

Tree debris:
This can be a contentious issue. Generally, a policy will pay to remove trees/limbs from an insured structure (home, shop, shed, fences, driveway ingress/egress) but only to the extent that access is restored to effect repairs. There may or may not be coverage to actually move debris to the curb and/or haul it off. There may be limited coverage for a tree struck by lightning, but in general there is no coverage for the value of trees (or any landscaping, for that matter). Certain limits apply in every case. Beware of tree contractors who state that "everything" is covered. "Everything" probably is not. Adjusters are issued tree debris guidelines for every storm.

Shop around for contractors as soon as possible. Check with your agent to see if your insurance company has a "preferred contractor" program (adjusters generally are not encouraged to extend this information, as it could create a conflict-of-interest). Remember that after every large insurance event, contractors from all over the country swarm to stricken areas. Some are qualified, some are not. Some pay local businesses to use their name temporarily. Ask lots of questions. Don't fall for the "We will absorb your deductible" sales pitch. This is a fraudulent practice and could land you in hotter water than Isaac experienced...much hotter.

It is common for insureds to politely offer food/drink/[other] to adjusters. Acceptance of these offers violates the adjuster's code of ethics, so consider preventing embarrassment by refraining from making such offers.

If the insurance company drops the ball you may file a complaint with your state department of insurance (this will get their attention in a heartbeat). Use this option with discretion, remembering that large events necessarily create chaos and logjams in the claims-handling process. For serious disputes, your policy mentions further steps (often some sort of arbitration). Worst case would be a public adjuster or attorney, due to their fees and/or timeliness; however, these are always an option. Just don't be a jerk and threaten your adjuster with legal action if you desire cooperation and a speedy resolution. Most unfavorable decisions are out of the adjuster's hands.

Above all, be patient. There are only so many hours in a day. In my case, I am generally working seven days a week up to 18 hours a day until my claim count diminishes. Don't create a s***storm by complaining to your agent over trivial stuff, as this creates a cascade of phone calls that wastes a lot of time. Larger claims are generally addressed first, so your sixty feet of downed fencing and small area of flooring damaged by water under the door are not going to be a huge priority. Try to be flexible with appointments and leave a large window for the adjuster, as he or she will have more than one inspection scheduled on any given day, and it is impossible to know in advance how long the inspection prior to yours will take.
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one lady reports.....Lots of trees and power lines still down and as winds gusts there's more to come. Earlier big tree staddled over 610 on ramp blocked access
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Quoting LargoFl:
downtown Biloxi....................

Looks like the Beau Rivage Casino?
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Quoting E46Pilot:
Man, Isaac is just sitting there. I've always said a Cat 1 storm can be just as bad as a stronger storm. Especially when it just sits there like that. The surge is topping the levees. They are holding but if they are not high enough that can be just as bad. Praying that Isaac gets moving and gets out of there real fast. Yes we have had flooding here in Palm Beach county but it's nothing compared to what they are going trough. Can't even imagine having head high water in the house.


Tropical Storm Allison had her name retired and was never a hurricane. Not so unusual for "weak" storms to be deadly and devastating.
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103. MahFL
oh oh, smaller eye has formed.
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Interesting spiraling patern in the eye:

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downtown Biloxi....................
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On TWC stephenie abrams was talking about the signs pointing different ways not the storm...
Do we know when he will start weakening? and why is 98L only at 50%?
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Quoting LAlurker:
Really, fellow bloggers, I know that many of you are tired of Isaac after 2 weeks of postings, but this is still going on here in LA, a lot still happening, still classed as a Cat 1 by NHC. Can you please refrain from posting about invests and TDs that won't affect anyone for days, weeks, or never. Give Isaac another day or two. Thanks!


Sorry to break it to you but there is life outside of LA and Isaac.

There are other blogs not to mention most of the media outlets that are dedicating much of their coverage on Isaac.

P.S. Masters mentioned 98L and Kirk in this blog. Should he not done so?
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Quoting LargoFl:
thanks for the info..you can just feel the strength of this storm huh..amazing

Oh yea. I lived in Ocean Springs MS during Katrina and had 8 feet of water in my house (I have since moved 15 miles north, 95 feet above sea level). Its blowing consistantly at about 35mph. There are areas along the beach that will certainly flood, but nothing compared to Katrina imho. On another note a person I work with lives near PATRAP, they are getting a good "blow" and everything south of I10 (Waveland and Pass Christian) is about unpassable
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97. CJ5
Everyone should be thankful he didn't have another 24 hours at sea. He looks almost as good as he ever has. Nice CDO, good eye wall structure. It was a close call.
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from Plaguemines parish..................
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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.