Hurricanes and Harvest Moon

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Seasons

Can cricket-song replace your garden thermometer? A harvest of fall weather information.

Nature's grandest storms, hurricanes, are heat engines that feed off the warmth of the ocean. Because ocean temperatures are at their highest in August and September, they are prime months for the most powerful of the mighty storms called "Atlantic" hurricanes.

A Little Respect

If you live anywhere within a hundred miles or so of Atlantic or Gulf of Mexico coastal waters, knowing some basics about hurricanes and hurricane safety could make the difference between life and death.

By definition, a tropical cyclone must have sustained winds of at least 74 mph to be classified as a hurricane. Even a hurricane with winds no stronger than this can be life threatening in certain circumstances. But a hurricane's "disaster potential" is measured on the five-level Saffir/Simpson Scale. On that scale (see table on page 28), a hurricane may have sustained winds as high as 95 mph and yet still be considered a "category 1" storm, the weakest of the five categories!

The greatest killer and destroyer in a hurricane is most often the "storm surge." This is the mass of ocean water piled high by the winds. In the strongest hurricanes, the height of the storm surge can exceed 20 feet. For such storms, massive evacuation of all low-lying residential areas within five to 10 miles of the shore is often required.

The date August 17, 1994, is the 25th anniversary of the landfall of the strongest (category 5) hurricane to have struck the U.S. mainland in the 20th century: Hurricane Camille. Neither of the more recent and infamous hurricanes to hit the United States, Andrew and Hugo, were nearly as strong. Camille produced estimated wind gusts of up to 200 mph, and destruction near its point of landfall was near total. The death toll along the Gulf Coast was 144. Out of the dozens of peo ple who decided to stay at a local hotel to have a "hurricane party," there was only one survivor—a woman who managed to cling to wreckage as it floated away.

Only one other storm has hit U.S. land with category 5 force in the 20th century: the Labor Day hurricane of 1935. When this hurricane struck the Florida Keys on September 2, it produced a lower barometric reading and therefore presumably even higher winds than Camille at the height of the storm, lifted vast quantities of sand into the air, became electrified, and glowed. Some of the estimated 400 victims of the storm were sandblasted to death, their bodies found scoured of both clothes and skin.

We shouldn't need such horror stories to remind us that hurricanes must be treated with respect. There are several important points to remember. If you live in an area at all accessible to hurricanes, now—not when a storm is already approaching—is the time to formulate your plans. By which roads and to which destination will you go if you have to evacuate? How will you protect your property whether or not you leave? What supplies should you have if experts deem it safe for you to remain?