What would have happened if Katrina hit 30 miles west?

[zlaxier]

How would the damage have been different in New Orleans and Mississippi?

Obviously, New Orleans would have had much more extensive wind damage, Cat 2 and 3 winds throughout the entire city instead of Cat 1 and Cat 2.

Would there have been flooding from the Mississippi River levees which there wasn't during Katrina? Would the Lake Ponchartrain levees have overtopped and collapsed sooner?

As bad as Katrina was in New Orleans, it was nowhere near the worst case scenario the NWS was predicting.

WWUS74 KLIX 282139
NPWLIX

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE NEW ORLEANS LA
413 PM CDT SUN AUG 28 2005

...EXTREMELY DANGEROUS HURRICANE KATRINA CONTINUES TO APPROACH THE MISSISSIPPI RIVER DELTA...
...DEVASTATING DAMAGE EXPECTED...

MOST OF THE AREA WILL BE UNINHABITABLE FOR WEEKS...PERHAPS LONGER. AT LEAST ONE HALF OF WELL CONSTRUCTED HOMES WILL HAVE ROOF AND WALL FAILURE. ALL GABLED ROOFS WILL FAIL...LEAVING THOSE HOMES SEVERELY DAMAGED OR DESTROYED.

THE MAJORITY OF INDUSTRIAL BUILDINGS WILL BECOME NON FUNCTIONAL. PARTIAL TO COMPLETE WALL AND ROOF FAILURE IS EXPECTED. ALL WOOD FRAMED LOW RISING APARTMENT BUILDINGS WILL BE DESTROYED. CONCRETE BLOCK LOW RISE APARTMENTS WILL SUSTAIN MAJOR DAMAGE...INCLUDING SOME WALL AND ROOF FAILURE.

HIGH RISE OFFICE AND APARTMENT BUILDINGS WILL SWAY DANGEROUSLY...A FEW TO THE POINT OF TOTAL COLLAPSE. ALL WINDOWS WILL BLOW OUT.

AIRBORNE DEBRIS WILL BE WIDESPREAD...AND MAY INCLUDE HEAVY ITEMS SUCH AS HOUSEHOLD APPLIANCES AND EVEN LIGHT VEHICLES. SPORT UTILITY VEHICLES AND LIGHT TRUCKS WILL BE MOVED. THE BLOWN DEBRIS WILL CREATE ADDITIONAL DESTRUCTION. PERSONS...PETS...AND LIVESTOCK EXPOSED TO THE WINDS WILL FACE CERTAIN DEATH IF STRUCK.

POWER OUTAGES WILL LAST FOR WEEKS...AS MOST POWER POLES WILL BE DOWN AND TRANSFORMERS DESTROYED. WATER SHORTAGES WILL MAKE HUMAN SUFFERING INCREDIBLE BY MODERN STANDARDS.

THE VAST MAJORITY OF NATIVE TREES WILL BE SNAPPED OR UPROOTED. ONLY THE HEARTIEST WILL REMAIN STANDING...BUT BE TOTALLY DEFOLIATED. FEW CROPS WILL REMAIN. LIVESTOCK LEFT EXPOSED TO THE WINDS WILL BE KILLED.

AN INLAND HURRICANE WIND WATCH IS ISSUED WHEN SUSTAINED WINDS NEAR HURRICANE FORCE...OR FREQUENT GUSTS AT OR ABOVE HURRICANE FORCE...ARE POSSIBLE WITHIN THE NEXT 24 TO 36 HOURS.

[ROCK]

I am sure there was a thread about this already...but for starters...probably more wind damage for sure with ALL of NO proper under water.

BTW- that NWS message was for KAT at cat 5 status. Better safe than sorry I guess...

[cajungal]

Well, I live 60 miles southwest of New Orleans. And Terrebonne Parish would look just like some parts of New Orleans and the MS coast right now. Hurricane Betsy hit Grand Isle in 1965 with the eyewall going straight over Terrebonne and Lafouche Parishes. I seen the photos and Houma-Thibodaux looked like a war zone. And St. Bernard Parish and the 9th ward were underwater. And we are now a lot closer to the Gulf of Mexico than we were in 1965. A lot of land has been lost since then.

[Audrey2Katrina]

Well, for starters, you'd have to move that enormous storm surge over to the west about 30 miles as well, and that would've in all likelihood spared Mobile and Pascagoula the enormous flooding they had, probably lessened the impact in Biloxi but it would've still been pretty bad from Gulfport to points west.

Tracking to the west instead of to the east of the city, I feel the winds coming from the South, instead of the north and east would've spelled much more damage from Lake Pontchartrain on the northshore than it was on the southshore.

The flooding would've probably been either the same or less as I doubt the surge in the Mississippi would've overtopped those levees which are much higher than those at the lake and seem to have been far stronger than the sloppy work done on the canals--which probably would have still breached--but to what extent remains entirely speculative.

Undeniably far greater wind damage. And Cajungal is right on target as the areas south and west of the city would have been devastated and inundated. In all likelihood the total $$ damage would be approximately the same as some areas badly damaged would have been spared, while others that were spared--would have been crushed.

A2K

[LaPlaceFF]

I would have been flooded out!!!!!!!

[MGC]

Jefferson and St Charles Parishes would be in the shape the Ninth Ward is in. The Mississippi coast would have still gotten a significant surge. The damage would be worst by another 100 billion.....MGC

[Audrey2Katrina]

Jefferson and St Charles Parishes would be in the shape the Ninth Ward is in. The Mississippi coast would have still gotten a significant surge. The damage would be worst by another 100 billion.....MGC

anything is possible in a speculative scenario; but having been there, I doubt that seriously. The worst part of the surge in the lake would have been directed toward the Northshore, not the southshore, hence I feel less flooding a distinct possibility.. but concede this is sheer speculation on both our parts. Let's hope we never find out.

A2K

[MGC]

A2K, with a landfall 30 miles futher west, a east wind would have forced even more water into Lake Ponchatrain. The surge would have been much greater. The levees in Jefferson Parish along the lake would have been over topped. The levees there were nearly over topped with a landfall east of the city. Imagine a 25 foot surge into the lake like the Miss coast got? Last time I was out at the lakefront in Kenner the levees were no where near that high. In one reguard New Orleans metro area was luck that Katrina did track east of the city. And don't forget that the west bank would likely get flooded by a westward track also. Can't forget my friends in Westwego.....MGC

[Derek Ortt]

also, those who took shelter in their attacks would have all been dead, as if cat 3 winds would have hit NO, the roofs likely would have been gone, forcing the people into the surge

[Audrey2Katrina]

A2K, with a landfall 30 miles futher west, a east wind would have forced even more water into Lake Ponchatrain. The surge would have been much greater. The levees in Jefferson Parish along the lake would have been over topped. The levees there were nearly over topped with a landfall east of the city. Imagine a 25 foot surge into the lake like the Miss coast got? Last time I was out at the lakefront in Kenner the levees were no where near that high. In one reguard New Orleans metro area was luck that Katrina did track east of the city. And don't forget that the west bank would likely get flooded by a westward track also. Can't forget my friends in Westwego.....MGC

I grant you that an eastern wind brings water into the lake--through a very NARROW inlet called the Rigolets; but bear in mind at the time Katrina made first landfall, she was already almost due south of the city and already "west" of the mouth of the Mississippi--those winds WERE from the east. The worst of that 5 surge was already pushing to the NORTH. The highest surges come with closer approach of the center, with most of the surge energy (remember created while it was still a 5 in the Gulf) given this scenario would be pushing up into Caminada Bay, Bayou LaFourche and Terrebonne Parish; (if anything Lafitte, and areas up to the Westbank Expressway would've looked like the MGC from the surge pushed up from the Gulf (a lot of those wetlands as buffers are no longer there--and THEIR canals would most certainly have breached)and the Rigolets might have been overwhelmed but I still doubt the surge actually making it into the lake on the southside would have been anything like what Mississippi got (remember they were like what the Northshore would've been--catching all the surge as the storm pushed NORTH. The surge from this storm was a massive swell moving NORTH and if anything the "Westbank" of Jefferson would have in all likelihood looked closer to the 9th than the more populous Eastbank (which would've gotten much worse wind damage). Undoubtedly still catastrophic; but I still feel the lake while higher, (especially north) would've impacted the Northshore and the Gulf surge the Westbank much more than the southshore.

IMO the true "worst case" would've been had a Katrina storm and subsequent massive surge had been coming in from the EAST, as was the case for the 1947 storm... now THAT would've overtopped the lake's levees on the southshore with a surge that size--undoubtedly. At least that's my opinion.

A2K

[Audrey2Katrina]

Oh.. not to mention the surge in Lake Borgne would've been much higher as well, resulting in worse, or at least higher flooding than already received in St. Bernard and the 9th--if that is even conceivable.

A2K

[Audrey2Katrina]

also, those who took shelter in their attacks would have all been dead, as if cat 3 winds would have hit NO, the roofs likely would have been gone, forcing the people into the surge

Metairie was virtually a ghost town. Sure, some stayed, even know a few; but nothing like the 100,000 that stayed in New Orleans.

A2K

[AussieMark]

IMO the true "worst case" would've been had a Katrina storm and subsequent massive surge had been coming in from the EAST, as was the case for the 1947 storm... now THAT would've overtopped the lake's levees on the southshore with a surge that size--undoubtedly. At least that's my opinion.

U mean this track

[Derek Ortt]

those who stayed in NO likely would have been dead had Katrina not weakened, and or it to the west

Also, about Katrina, I am glad she hit Florida when she did. 24 more hours over the water, Katrina likely levels Miami as well

[Audrey2Katrina]

IMO the true "worst case" would've been had a Katrina storm and subsequent massive surge had been coming in from the EAST, as was the case for the 1947 storm... now THAT would've overtopped the lake's levees on the southshore with a surge that size--undoubtedly. At least that's my opinion.

U mean this track

EXACTLY... Had Katrina come in THAT way, we'd have had a calamity in terms of human deaths that would have dwarfed the horrors of even the Galveston storm of 1900... my guess: at least 90,000 to 125,000 dead. Mostly because she wouldn't have likely weakend as much, and those surges would've swamped all those remaining in ALL eastbank areas before any rescuers would've had any chance to get to them.

A2K

[TSmith274]

30 miles west would have just about been the worst case scenario. Not only would Lake Ponchartrain fill with water, but the Barataria Basin would have also filled. The Barataria Basin leads up to the westbank of Jefferson and Orleans Parishes. The Levees on that side of the metro area make the levees that failed in New Orleans look like fortresses. 100% of the city would have flooded, including the suburbs. Lets hope this never happens. Or, we can prevent it by investing in true area-wide real levee protection.

[Ixolib]

WWUS74 KLIX 282139
NPWLIX

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE NEW ORLEANS LA
413 PM CDT SUN AUG 28 2005

...EXTREMELY DANGEROUS HURRICANE KATRINA CONTINUES TO APPROACH THE MISSISSIPPI RIVER DELTA...
...DEVASTATING DAMAGE EXPECTED...

MOST OF THE AREA WILL BE UNINHABITABLE FOR WEEKS...PERHAPS LONGER. AT LEAST ONE HALF OF WELL CONSTRUCTED HOMES WILL HAVE ROOF AND WALL FAILURE. ALL GABLED ROOFS WILL FAIL...LEAVING THOSE HOMES SEVERELY DAMAGED OR DESTROYED.

THE MAJORITY OF INDUSTRIAL BUILDINGS WILL BECOME NON FUNCTIONAL. PARTIAL TO COMPLETE WALL AND ROOF FAILURE IS EXPECTED. ALL WOOD FRAMED LOW RISING APARTMENT BUILDINGS WILL BE DESTROYED. CONCRETE BLOCK LOW RISE APARTMENTS WILL SUSTAIN MAJOR DAMAGE...INCLUDING SOME WALL AND ROOF FAILURE.

HIGH RISE OFFICE AND APARTMENT BUILDINGS WILL SWAY DANGEROUSLY...A FEW TO THE POINT OF TOTAL COLLAPSE. ALL WINDOWS WILL BLOW OUT.

AIRBORNE DEBRIS WILL BE WIDESPREAD...AND MAY INCLUDE HEAVY ITEMS SUCH AS HOUSEHOLD APPLIANCES AND EVEN LIGHT VEHICLES. SPORT UTILITY VEHICLES AND LIGHT TRUCKS WILL BE MOVED. THE BLOWN DEBRIS WILL CREATE ADDITIONAL DESTRUCTION. PERSONS...PETS...AND LIVESTOCK EXPOSED TO THE WINDS WILL FACE CERTAIN DEATH IF STRUCK.

POWER OUTAGES WILL LAST FOR WEEKS...AS MOST POWER POLES WILL BE DOWN AND TRANSFORMERS DESTROYED. WATER SHORTAGES WILL MAKE HUMAN SUFFERING INCREDIBLE BY MODERN STANDARDS.

THE VAST MAJORITY OF NATIVE TREES WILL BE SNAPPED OR UPROOTED. ONLY THE HEARTIEST WILL REMAIN STANDING...BUT BE TOTALLY DEFOLIATED. FEW CROPS WILL REMAIN. LIVESTOCK LEFT EXPOSED TO THE WINDS WILL BE KILLED.

AN INLAND HURRICANE WIND WATCH IS ISSUED WHEN SUSTAINED WINDS NEAR HURRICANE FORCE...OR FREQUENT GUSTS AT OR ABOVE HURRICANE FORCE...ARE POSSIBLE WITHIN THE NEXT 24 TO 36 HOURS.

This scenario also brings up another point. With this kind of WARNING, where virtually every word and phrase is in the extreme, it may contribute to the sense of complacency that we often talk about. Almost every sentence in the above warning is provided in absolute terms, bringing the implication that the results WILL be exactly as indicated. As we all know, many of those scenarios did not pan out, consequently folks may think they (or their property) actually survived an event that they did not. Yeah, I know - and everyone here knows - that this warning is based on a CAT 5, but the general public probably does not. And even if it was a CAT 5, would every single one of those scenarios actually happened? How do "they" know with such certainty that these extreme absolute consequences will in fact take place?

My question is this. Why does/did the NWS issue such an absolute and extreme warning? In the history of hurricane tracking, has every one of those possibilities actually occurred someplace? What highrise buildings have actually swayed to the point of collapse??? In what landfalling hurricane have "ALL GABLED ROOFS FAILED"? When have "ALL LOWRISE APARTMENT BUILDINGS" been destroyed? When and where have ALL windows actually blown out? And so on and so on...

Point being, what history is this kind of warning based on - especially when given in such absolute terms? Or, is this kind of warning just supposition based on the SS Scale - which is becoming questionable at best in its accuracy....

Reminds me of the posters here who say "this city will be LEVELED" or "that city will be COMPLETELY DESTROYED", etc. Never have a I seen any footage of an area that truly matches up with the absolute and extremes in this NWS statement....

[skysummit]

30 miles west would've taken my home away. The locals here were talking about 10 feet of water in downtown Houma if she did not turn. EVERYTHING south of Lake Ponchartrain would be under water....pretty much the Gulf and the Lake would have joined. All windows in the tall buildings in NOLA would be blown out with many, if not all having extensive damage. The rest of the Superdome roof would be gone and the Saints would have their open air stadium they always wanted.

[tailgater]

I'd like to add to the debate of MSG and A2K, the winds of the 48 hrs. before landfall along the Miss. and SE. La. coast were from the NE according to the historical data.
So IMHO 30 degrees of more Lat. ie. ( coming in from the Yucatan channel)would have a far greater impact on both coast, including the GNO. SE winds piling up more water in the Ponchatrain basin.

[Ixolib]

The Saints would have their open air stadium they always wanted.