Slow-Moving Hurricane Isaac Pummels Louisiana

By Michael D. Lemonick

Although it made landfall more than 12 hours earlier, Hurricane Isaac continued to pummel southern Louisiana Wednesday morning as the huge Category 1 storm stalled in its motion to the northwest.

New Orleans’ system of flood-protection levees and canal floodgates, upgraded to the tune of $14.5 billion after the system’s catastrophic failure due to Hurricane Katrina in 2005, continued to hold against the wall of water pushed onshore by the storm — a surge that reached 11 feet in Shell Beach, La., according to Brian McNoldy’s Tropical Atlantic Update, 8 feet in Bay St. Louis, Miss., and 4 feet in Mobile Bay, Ala.

Credit: NOAA

But the drawn-out pounding, combined with torrential rains that had already dumped 10 inches of extra water across much of the region, continued to test the levees’ limits, along with flood protection systems protecting the swath of shoreline hundreds of miles across where Isaac’s effects are being felt.

Isaac’s sustained winds of 80 mph, meanwhile, howling for hours on end, have knocked out power to more than half a million people in Louisiana so far, and thousands more in Mississippi and Alabama. Repair crews can’t begin to work on restoring electricity until the winds drop below 30 mph, so the number is certain to grow as the storm continues to grind away at southwestern Louisiana and slowly moves to the northwest.

In its Wednesday morning update, the National Hurricane Center announced that this forward motion had finally begun, but at a glacial pace of just 5 mph. By Wednesday evening, Isaac was predicted to be downgraded to a tropical depression, with torrential rains and sustained winds at a still-dangerous 65 mph. By Thursday evening, said the Hurricane Center, Isaac should be crossing into Arkansas as a tropical depression, with 35 mph winds, and still heavy rains.

Those rains, at least, could be a blessing for parched Arkansas, where significant parts of the state have been suffering extreme drought as part of the nation’s worst dry episode since the 1950’s.

Isaac’s projected path should put it in Missouri by Saturday, Indiana by Sunday and over the Indiana-Ohio border by Labor Day. The storm will be far weaker by then, but forecasters are calling for potentially heavy rains across a wide path through the nation’s midsection.

It won’t be enough to make up for the summer-long drought, and the rains will come too late to help the corn and soybean crops devastated by the lack of water. But it comes just in time, according to report by Reuters, to give hope for the fall wheat planting season.