Katrina warning

Ok people get out now. If you know a poor person that needs a ride. Take them with. The superdome is 9 feet below sea level.

CATASTROPHIC HURRICANE APPROACHING NEW ORLEANS REGION

NHC WARNINGS:

Hurricane Warnings :
NORTH CENTRAL GULF COAST FROM MORGAN CITY LOUISIANA EASTWARD TO THE ALABAMA/FLORIDA BORDER...INCLUDING THE CITY OF NEW ORLEANS AND LAKE PONCHARTRAIN.

Tropical Storm Warning & Watches: A TROPICAL STORM WARNING AND A HURRICANE
WATCH HAVE BEEN ISSUED FROM EAST OF THE ALABAMA/FLORIDA BORDER EASTWARD TO DESTIN FLORIDA...AND FROM WEST OF MORGAN CITY TO
INTRACOASTAL CITY LOUISIANA.

A TROPICAL STORM WARNING IS ALSO IN EFFECT FROM DESTIN FLORIDA TO INDIAN PASS FLORIDA AND FROM THE INTRACOASTAL CITY LOUISIANA WEST TO CAMERON, LOUISIANA.

NOTE: My Advisory Service is for Informational Purposes only -- You are STRONGLY urged to follow the directions of all Emergency management, Police and Governmental Agencies in your area as it relates to the protection of lives and property - regardless of what my Storm Updates may imply.
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CURRENT POSITION / NOTEWORTHY REPORTS PAST HOUR

KATRINA LOCATED 26.1N / 88.1W or 290 miles SSE of Gulfport, MS. - 275 miles SSE of downtown New Orleans - and 240 miles SSE of Port Eads at the southern tip of the Mississippi Delta. Katrina is heading just north of DUE Northwest at 9Kts (10 MPH) over the past 2 hours

RECON Reports:

Pressure 907mb ( DOWN 42MB IN 24 HRS)
MAX Flight Level wind 166KTS - SUSTAINED SURFACE WINDS 175MPH - GUSTS TO 200MPH.

EYEWALL DIAMETER IS STEADY AT 22NM
CREW REPORTS 'PERFECT STADIUM EFFECT'

Hurricane Katrina is now as strong as Hurricane Camille in 1969 - but this storm is larger, and will cause more extensive damage, and if it strikes New Orleans at 'just the right angle' - will no doubt MAY lead to the greatest loss of life from a land falling hurricane in nearly 100 years.

The exact track - and even the exact intensity of Katrina at landfall is still simply too difficult to predict with the type of precision everyone would like. As discussed extensively over the past few days, the overall environment surrounding Katrina was expected to become as conducive to the development of a CAT 5 hurricane that scientists are able to determine. One o the biggest 'unknowns' - and lowest skill forecast - are for storm intensity. Ironically, this is especially true when trying to forecast intensities in the near-term -- 24 hours or less.

Unlike Track forecast accuracy, which improves as the time of landfall approaches, intensity forecasts exhibit only slightly better skill than pure chance, when in the 0-24 hour outlook period. MANY factors come into play that
cause this, including the fact that we still do not know 'everything' we need to know about how hurricane work.

As a result, one of the biggest changes that occur with a hurricane that affect intensity are the eye wall replacement cycles - also talked about extensively in the past 2 days. There is no real telling when an eye wall replacement cycle will start, or how long it will last. However, the first signs of it are normally when the eye diameter starts shrinking to near or below 10NM.

Last night, when Katrina bean intensifying rapidly, the eye was 40NM across. Even around 2AM, the eye had only shrunk to 38NM, yet the pressure had already fallen to 935mb. I have never seen (in 35 years of watching) a storm
of such intensity, with such a large eye. 5 hours later, we find an eye that is 22NM across, and the pressure has fallensome 28mb -- and the winds responded immediately by increasing to a strong CAT intensity.

The question is - will the eye continue to shrink over the coming hours (which by the way would cause the winds to increase even more all things being equal) -- and then cause the storm to enter an eye wall replacement cycle. What could be a 'fooler' is that the eye might get down to around 15NM-18NM and then start to re-cycle. We are in uncharted territory in this regard. The '10NM or less rule of thumb' may not apply to what is about the most intense hurricane in recorded history (in the Atlantic basin). In any event, once the eye wall goes through regeneration, the pressure will rise, and the maximum winds will decrease as the developing outer eyewall will be of much greater diameter. A replacement cycle can run from 6 to 18 hours. Another possibility, is that Katrina may start doing a different variation on the theme - that is - rapid eye wall cycling. VERY intense hurricanes have done this before.

IVAN went through this type of rapid cycling while in was in the Caribbean. This is where the eye shrinks to near 5-8NM while a new wall forms at around 15NM. This replacement cycle lasts for 2-4 hours -- and the period of slightly higher
pressure, and lower winds is relatively brief. This may have the highest probability of happening. No doubt this entire process is related to why historically, Atlantic basin Hurricanes rarely can maintain CAT 5 intensity for very long periods.

By the time a 12 or 18 cycle completes, the storm is many times in an area that is not as favorable for re-intensification.
Either the water temps are cooler, or the vertical shears are a bit higher, or the storm is closer to land. There is only a
VERY REMOTE possibility that Katrina will not have at least 1 eye wall replacement during the next 24 hours.

Below are some recent Buoy reports (about 1 hour ago). Note that the storm surge from Katrina is NOT the same thing as sea swell or wave heights. The storm surge is totally different, and relates to how much the entire ocean rises above normal
tidal height. Similar to a Tsunami. ON TOP of the storm surge, will be the wind driven waves. These wave heights are what are being shown below, and will be what I pass along as the storm approaches. IVAN produced a wave height of 70 feet that destroyed an oil platform. Katrina, IF IT MAINTAINS ITS CURRENT INTENSITY, will cause wave heights of 80-100 feet over the open ocean -depending on just how fast the storm is moving by any given area at the time. The full force winds of 175mph, and gusts to 200mph is likely only occurring across an arcing shaped rectangular area roughly 5 miles wide by 30 miles long, adjacent to the NE portion of the eyewall. That is the area where the 80-100ft waves would
be occurring. Assuming Katrina cuts across the Delta with the TRUE CENTER passing over Borne at it's current intensity, a 24-28 foot storm surge will hit the Delta and the Bay St. Louis area, where wind driven waves will be about 50 feet.

Because of the extraordinary nature of this event -- my updates will vary considerably from 'normal'. Only highly relevant images and analysis will be provided. I will attempt to issue 1 'Major Update' around 8PM CDT tonight.

To maximize peoples ability to see 'the whole story' - my blog postings will tend to be 'updates' only to each post - versus starting an entirely new post. An update to this Advisory with the latest computer model run data will be sent in about 1 hour.

Steve Gregory

BUOY REPORTS

42001 180NM South of Southwest Pass, LA Winds N 37Kts Gust 47Kts 20 foot sea swells
42007 - 22NM SSE of Biloxi, MS Winds E 25Kts Gust 29Kts / 12 foot sea swells
42039 (115NM ESE Pensacolal) Winds E 27Kts Gust 37Kts / 19 foot sea swells
42040 (64NM South of Dauphin Island) Winds ENE 25Kts Gust 33Kts / 17 ftoot sea swells