LOS ANGELES, CA (Catholic Online) - Tropical Storm Isaac is expected to make landfall as a Category 1 hurricane, bringing along with it a storm surge of between 6 and 12 feet. The hurricane is closing in on New Orleans and the entire Louisiana coast, and is expected to touch down Tuesday night or early Wednesday.

"We fully expect that we will get the brunt of it," New Orleans Mayor Mitch Landrieu said. "We think that we're well prepared," he added, while emphasizing that much depends on how well residents heed warnings to hunker down.

National Hurricane Center Director Rick Knabb says that "rain bands will become more frequent and more potent" along the northern Gulf of Mexico coast.

Very wide as storms go, Isaac features tropical storm-force winds stretching as much as 205 miles from its center. Coupled with its size and slow motion, Knabb says that a large storm surge, in particular in southeast Louisiana where surges up to 12 feet are predicted.

The fact that a tropical storm's winds move counterclockwise will make matters worse. The city of New Orleans will suffer the brunt if Isaac makes landfall to the west of the city as some models suggest.

"That counterclockwise direction is really a big problem," NBC meteorologist Al Roker says. "As it continues to bring in those winds from the southeast it's going to be piling water up." Rainfall of seven to 14 inches across the coast as well as inland is likely, and a few places could even see 20 inches.

Haunted by the devastation of Hurricane Katrina seven years ago, residents are fleeing for higher ground. Officials say stronger and higher defenses built since Katrina will hold.

New Orleans' levees built or repaired after Katrina are designed to withstand far more than that 12-foot surge, in some cases storm surge as high as 26 feet.

Residents should expect "a lot of hazards to contend with, even isolated tornadoes" Knabb said.

In the meantime, mandatory evacuations were issued yesterday for unprotected, low-lying areas outside New Orleans, as well as low-lying areas in Mississippi.

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