Hurricane Gustav bad weather news

A woman uses a poncho to keep dry as she walks through rain caused by Tropical Strom Gustav in Port-au-Prince, Monday, Aug. 25,2008. Haitians were told to prepare for evacuations as Tropical Storm Gustav formed quickly Monday in the Caribbean on a path to hit as a hurricane the country's denuded southern coast before moving on to Cuba, the Bahamas and Florida. (Ariana Cubillos/AP Photo)

Tropical Storm Edouard Threatens Louisiana

Fifth Storm Of The 2008 Hurricane Season Forms In The Gulf Of Mexico

NEW ORLEANS, Aug. 3, 2008

This infared satelite image from the National Oceanic And Atmospheric Administration shows Tropical Storm Edouard off the coast of New Orleans on Aug. 3, 2008. (NOAA)

Tropical storm Fengshen

Typhoon Lashes Philippines, Ferry Capsizes

Hundreds Of Passengers Feared Dead; Death Toll From Storm Put At 163

Despairing survivors of cyclone Nargis sit at a refugee centre in the town of Labutta, Myanmar, on Saturday awaiting international aid shipments.

Weather predictions or not? Most fail to materialise

Fort Collins, Colorado _ Last week, daily forecasts told weather worry-warts for five straight evenings that heavy snow was likely on the next afternoon, and five afternoons passed, sunny and rather pleasant winter days. And on the sixth day, it snowed heavily.

Maine Region braces for stormy weather as Hurricane Noel turns into a nor'easter today.

Typhoon Krosa hits East China, one mln evacuated see the video

related Supertyphoon Krosa Nears Taiwan

In Jamaica, People Are Preparing for Hurricane Dean, Sunday August 19, 2007 | REUTERS/CARLOS BARRIA

Here's what travelers need to know about Hurricane Dean :

Hurricane travel tips
Dean's wobble a tell tale sign

People Are Preparing for Hurricane Dean,
Sunday August 19, 2007
picture: REUTERS/CARLOS BARRIA

by Mark Schleifstein Sunday August 19, 2007, 2:27 PM found at The Times-Picayune

As Hurricane Dean rakes across Jamaica today on its way to a potentially disastrous date with the Yucatan Peninsula early Tuesday morning, it's showing the tell-tale characteristics of a maturing major cyclone.

hurricane Dean Aug19 2007 Dean lost some strength overnight, the probable result of an eyewall replacement cycle. On Saturday, two eyewalls were clearly visible in the center of the storm.

By midnight, only one, and an Air Force Reserve Hurricane Hunter aircraft reported the eye as less distinctive, with warmer cloudtops.

This cycling is routine in major hurricanes, as the eyewall and its maximum winds contract smaller and smaller. Rainbands just outside the eyewall grow together into a new ring, robbing the interior eye of moisture and energy, and eventually replacing it.

As can be seen with Hurricane Dean, the cycle usually ends with the storm strengthening again.

The other characteristic being shown by Dean is what forecasters Richard Pasch and Dan Brown referred to as "trochoidal wobbles" and what I call "crazy Ivans," (As in Tom Clancy's "The Hunt for Red October")

Think of the hurricane as a top moving across a tabletop, and someone blows on it or touches it, changing its course for a moment. Differences in the distribution of rainfall within the storm, or changes in wind shear, or the way in which the eyewall replacement occurs creates a momentary zig or zag, and is a major reason why hurricane forecasts cover six-hour periods - to even out the wobbles.

Today's forecasts discount the effects of such motions, relying on the expected continued growth of a high pressure ridge over the United States to continue to push Dean west over the next few days.

The forecast calls for Dean to hit Category 5 strength before its eye goes ashore south of the island of Cozumel and the resort city of Cancun on Mexico's Yucatan Peninsula. The likely target at the moment is the Sian Ka'an Biosphere Reserve, near the Mayan Ruins of Tulum. The reserve's beaches, swamps and mangroves sit along a 70-mile stretch of barrier reef.

Dean will weaken significantly, as its path is predicted to have moved south enough to keep much of the storm over the peninsula as it crosses into the Bay of Campeche.

But warm water there will help it regain strength to at least a Category 3 storm weather before going ashore again south of the Mexico-Texas border near Tampico.

A reminder that I'm not a meteorologist, and you should use the National Hurricane Center's official forecast for planning purposes.

Mark Schleifstein is The Times-Picayune's environment and hurricane reporter, and co-author of "Path of Destruction: the Devastation of New Orleans and the Coming Age of Superstorms." He can be contacted at 504-826-3327, or mschleifstein@timespicayune.com
Related Radio Bush