At one point Hurricane Rita was the third most powerful hurricane on record for the Atlantic Basin, which includes the Gulf of Mexico. The storm's strongest winds reached 175 miles an hour (280 kilometers an hour) Thursday morning.
Since then the storm has lost some of its frightening intensity, but forecasters still think it will come ashore with winds of 120 to 130 miles an hour (190 to 210 kilometers an hour).
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The hurricane also will drive a dangerous storm surge into the coastal rivers and bays of Texas and Louisiana. Rinard said the peak of the surge near Rita's center could be 15 to 20 feet (4.5 to 6 meters).
"This surge will be felt quite a ways inland," he said.
Even before today's new levee break, Hurricane Rita had rekindled fears that New Orleans would be flooded once again. About 80 percent of the city was flooded when the levees failed last month.
The U.S. Army Corps of Engineers had worked feverishly to repair the levees and pump floodwaters out of New Orleans. Although the city will not see anything like the blast it received from Katrina, even a little wind and rain has been causing problems.
"The infrastructure is still fragile," said Paul Trotter, the meteorologist in charge of the National Weather Service office in Slidell, Louisiana. "Anything that's going to mess with the infrastructure now that it's so delicate and fragile could cause some unpleasantries."
Hurricane Rita could dump 3 to 5 inches (8 to 13 centimeters) of rain in the New Orleans area and bring winds exceeding 40 miles an hour (64 kilometers an hour), Trotter said.
A few days ago forecasters expected the storm's center and its storm surge to come ashore at or near Galveston Bay. That would have meant a direct hit on Houston, the nation's fourth largest city.
"If Rita had tracked a little farther west, that would have been the worst-case scenario for our area," Wong of the weather service's Houston-Galveston office said.
A hurricane's front-right quadrant contains its strongest winds and peak storm surge, and it is more likely to produce tornadoes as it comes ashore. Residents of coastal Texas refer to the front-right quadrant as the "dirty side" of a hurricane.
If the dirty side of a strong storm like Rita were to hit Houston-Galveston, the results would be catastrophic. The storm surge could easily top the seawall protecting Galveston and put the island city underwater. The surge also could send waters from Galveston Bay surging through Houston.
If Rita's eye makes landfall up the coast from Houston, as predicted, the city will be spared such devastation. The backside of the storm might actually lower the water level in Galveston Bay because the winds will be blowing water away from the city.
Willie Drye is the author of Storm of the Century: The Labor Day Hurricane of 1935, published by National Geographic.
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