Skip to comments.ALERT: Hurricane Isidore forecasted to have at least 150 MPH winds within 72 hours
Posted on 09/21/2002 3:05:23 PM PDT by newsperson999
Statement as of 5:00 PM EDT on September 21, 2002
Air Force recon data indicate major Hurricane Isidore has continued to rapidly strengthen and the central pressure has dropped 21 mb in the past 13 hours. A pressure of 946 mb generally corresponds to a maximum wind of about 117 kt. However...the eye is open to the west and there may be a lag in the wind field. Also...dropsonde data indicated about 105 kt surface winds...but winds just a few hundred above the surface have been as high as 130 kt. The three satellite agencies reported a Dvorak satellite intensity estimate of t6.0...or 115 kt...while the 3-hour objective Dvorak T-number was also t6.0. Based on this information...the initial intensity was increased to 110 kt.
The initial motion estimate is 270/3. Recon fix positons since about 12z indicate Isidore has actually remained nearly stationary the past 6 hours...but right over some of the hottest water in the Atlantic Basin. Steering currents remain weak and are forecast by all of the global to remain weak or even get weaker. Isidore remains caught between a mid- to upper-level low east of Florida and one to the west over the Bay of Campeche. A weak and narrow low- to mid-level ridge extends across the northern Gulf of Mexico coast from Florida westward to Texas. Given the relative weakness of this ridge...only 5880 meters at 500 mb...it would not take much of a shortwave trough to erode it and allow Isidore to drift slowly poleward. All of the NHC model guidance...except LBAR...keeps Isidore moving on a slow west or west-southwest track through the forecast period. The AVN and GFDL are very similar in hooking Isidore to the southwest around the western Yucatan Peninsula in 36 to 48 hours. This may be some artifact of terrain interaction which I have ignored for this advisory package since all of the global models show no significant ridging north of isiodre to push the system to southwest. The forecast calls for a slow...less than 6 kt...motion throughout the forecast period with a slight west-northwestward motion after 48 hours as a strong shortwave trough drops down the west side of the broad longwave trough...which is expected to erode the weak ridge over Texas and the northwest Gulf of Mexico and allow Isidore to gain some latitude. However... the slower Isidore moves during the next 36 to 48 hours will determine just how far north and the cyclone will move in the longer time periods beyond 72 hours. The good news is that it appears that Isidore is not going to go anywhere fast. The bad news is that it will remain over very hot water.
The central pressure has dropped 21 mb in the past 13 hours. A typical rapid intensification period. This trend would normally continue for another 12 hours or so...but radar and recon data indicate that the eye is open to the west and that an eyewall replacement cycle may be starting. As such...the official intensity forecast is held below the ships intensity model which brings Isidore to 135 kt in 36 hours and 140 kt in 60 hours. This type of intensification is certainly possible given the low shear...less than 6 kt...and high SSTs...about 30c/86f. However...predicting internal convective changes is nealry impossible so there could be flucuations by as much 10 kt either way from the offical intensity forecast. Some coastal upwelling may weaken the hurricane slightly as it moves west of 88w longitude...but then some restrengtnening is forecast after 48 hours when Isidore is forecast to move back over warmer water.
forecast positions and Max winds
initial 21/2100z 21.9n 86.2w 110 kts
12hr VT 22/0600z 21.9n 87.0w 120 kts
24hr VT 22/1800z 21.9n 88.0w 125 kts
36hr VT 23/0600z 21.9n 89.2w 125 kts
48hr VT 23/1800z 22.0n 90.3w 125 kts
72hr VT 24/1800z 22.5n 92.5w 130 kts
also tropical depression 13 has formed and is foreasted to develop into a hurricane as it moves into the westren Carribean sea in 72 hours.
For sale: property along the gulf coast - cheap. All inquiries responded to real quick! We're outta here.
Here's the NOAA forecast. This storm will threaten Brownsville and give Tejas a good soaking.
By BOB ANDERSON
Hurricanes could inundate many inland cities and communities in Louisiana that consider themselves safe from the great domes of water pushed ahead of the storms, LSU researchers say.
Advocate photo by Bob Anderson
Even a category 3 hurricane, with winds up to 130 mph, could push a storm surge over New Orleans' hurricane protection levees, like this one, and into the city, which has many areas below sea level, LSU researchers say.
And it would only take a category 3 storm, packing winds of up to 130 mph, to shove such a massive surge through Lake Pontchartrain into New Orleans, much of which is below sea level, their computer models indicate.
The wrong storm could put 20 ft of water in Jackson square, leaving the statute of Andrew Jackson under water, said Robert Eichhorn, director of emergency management for New Orleans.
"If you don't evacuate New Orleans, the best thing you can do is tie a tag around your toe so we can identify your body," said Brett Krieger, director of the state Office of Emergency Preparedness.
Hurrican season officially started Sunday.
Evacuating people into most tall buildings would be sending them into "death traps," where winds could blow glass and people out of the buildings, Eichhorn said.
A category 3 storm would put most of St. Bernard, Terrebonne, Jefferson, St. John, Lafourche, St. Charles and St. Mary parishes under water.
It would even flood large parts of Livingston, Iberville, Ascension, Assumption, Tangipahoa, St. Martin, and St. Tammany parishes, the computer model indicates.
The amount of flooding a storm can cause in a given area depends on its strength, its track and its forward speed, with slow moving storms pushing more water ahead of them, said LSU engineering Professor Joe Suhayda, who is running new storm surge models for emergency officials.
A category 5 storm, with winds over 155 mph, running up the middle of the state would flood everything up Bayou Lafourche for more than 70 miles as far as Napoleonville.
The surge from that same storm would flood Houma and Thibodaux, which is more than 30 miles from the coast, and push water to the outskirts of Plaquemine, the model indicates.
Just about everything south of Interstate 10, populated by 2.2 million people is now subject to hurricane flooding, Suhayda said.
Danger to south Louisiana is growing worse because of development and land loss, coastal specialists said.
Deterioration of barrier islands and coastal marsh, combined with land subsidence and sea-level rise are making Louisiana ever more vulnerable, said LSU coastal researcher Ivor Van Heerden.
While all of south Louisiana is at risk, the storms with the potential to kill the most people are ones that shove huge surges into Lake Pontchartrain, which has heavily populated areas on its north and south shores.
"Most people have the misconception that the threat to New Orleans is from the Gulf, but the threat is really from the lake," said state Climatologist Jay Grymes.
New Orleans should be viewed as a coastal city much of which is below sea level, officials said.
A hurricane could rapidly push an 18-foot-high surge into the lake, the models run by Suhayda show.
The work of another LSU researcher, Greg Stone, adds a frightening dimension:
Hurricane surges in Lake Pontchartrain could be topped with waves of up to 10 feet.
Neither the seawall at Mandeville nor the hurricane protection levee at New Orleans could handle the kinds of storm surges Suhayda's models project, even without the waves atop them, emergency officials concede.
A surge is a gentle rise compared to the waves on top of it, which can batter buildings and other structures, Suhayda said.
The waves make it easier for surges to wash over and damage hurricane levees and buildings and to block evacuation routes, Stone said.
Waves atop storm surges could pound over the Causeway's guard rails hours before the eye of a storm ever reached New Orleans, he said.
Combined with the flooding hurricanes have shown that they can cause along I-10 in both directions from New Orleans, the high waters and waves could further shorten the window of evacuation for the city, researchers said.
Emergency officials concede that complete hurricane evacuation of New Orleans is unrealistic, saying it would take three days notice and overcoming apathy to even come close.
The combination of a large population and a limited road system that floods makes evacuation difficult, according to officials with the Jefferson Parish Emergency Operating Center.
Andrew, a category 4 hurricane, with winds from 131-155 mph, was just a tropical storm 72 hours before it hit Louisiana in 1992. Hurricane specialists can't accurately predict how big a storm is going to be or where it will hit land that far ahead of time, Krieger said.
Even though it was obvious Hurricane Andrew posed a severe threat to New Orleans before it settled on a course through the Atchafalaya Basin, "people didn't really start to leave until 16 hours before Andrew hit," Krieger said.
Starting that late leaves only a few hours before the evacuation has to be stopped to prevent people getting trapped on the Causeway or I-10, he said.
Because of the damage Andrew caused in Florida, more people got out of New Orleans than usual, but still only 13 to 14 percent evacuated, Eichhorn said.
People who have remained dry behind hurricane protection levees during small or distant storms may not realize how drastically things can change once a section of that levee fails.
"People were found drowned in their attics after Hurricane Betsy, because places went from having no water to having 20 feet of water in 15 minutes," Krieger said.
Levees "do a very good job in protecting communities in minimal hurricanes," a National Weather Service report says, but adds, "most levees in southeast Louisiana would be overtopped from a direct strike by a slow moving, major hurricane."
The Red Cross has decided it's too dangerous to provide hurricane shelters in New Orleans or anywhere south of I-10, but the state will supply some last minute survival sheltering for people who don't leave the city, Krieger said.
The idea will be to try to get them into the most stable buildings and high enough so they don't drown, but the quick influx of water when levees are topped is still likely to cause widespread loss of life, Krieger said.
Disease could follow the storm as emergency officials deal with unsanitary conditions, lack of drinking water and standing flood waters, he said.
It could take three days for help to reach some of these people, Eichhorn said.
That is not stress or bad pizza. It is exactly one of the ways G~d warns people, or warns some so they can warn others. You are only seeing a storm, others are having dreams and visions of major earthquakes, mushroom clouds, missiles, invading armies and worse. Today is a good day to repent.
Joe 2:28 And it shall come to pass afterward, that I will pour out my spirit upon all flesh; and your sons and your daughters shall prophesy, your old men shall dream dreams, your young men shall see visions:
29 And also upon the servants and upon the handmaids in those days will I pour out my spirit.
30 And I will shew wonders in the heavens and in the earth, blood, and fire, and pillars of smoke.
31 The sun shall be turned into darkness, and the moon into blood, before the great and the terrible day of the LORD come.
32 And it shall come to pass, that whosoever shall call on the name of the LORD shall be delivered: for in mount Zion and in Jerusalem shall be deliverance, as the LORD hath said, and in the remnant whom the LORD shall call.
Her dream took place in Israel. She was underground in a Jewish bomb shelter while a war was going on above. She isn't Jewish... but the Jews were protecting her. I was in a city where a war was being fought; buildings had craters in them; people were running in fear. Fours horses were galloping through the street below my office window. I know what four horses mean.... and it freaked me out.
This, of course, has nothing to do with the 24 x 7 imagery beamed into your home I guess.
Sometimes I think there are always two true answers to every question and you get to choose which one you want to listen to. Something to do with free will....
Askel5, see if you can get me about five of those 'toe tags.' blam + 4 doggies. (lol)
Your as witty as you are ignorant of North American geography. Granted it's hard for some to fathom a state that measures 840 x 660 miles. Crawford is closer to Dallas to the NE and Amarillo to the NW. Crawford doesn't get much rain being in the western half of Texas. It is more desert than anything. So this hurricane means a better deer season and that's about it out west.
Down along the coast, folks could be majorly screwed. Being inland along the I-10 prarie west of Houston we could expect prolonged power outages and nowhere to go to work downtown. Some models indicate an intense hurricane could move up the ship channel do a 180 move out and more up to the west again to finish off much of the city. 18 ft of water could accumulate in downtown Houston, much of it tainted with lead, arsenic and mercury from the stirred up ship channel sediment. People in Galveston would find themselves stranded and fighting with snakes and other nasties on the highway overpasses and other higher elevation spots.
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