"Yes, it seems slow compared to the last couple of years, but this is nothing out of the ordinary," said Dennis Feltgen, spokesman for the National Hurricane Center in West Miami-Dade County.

Many a hurricane season has started slowly, only to accelerate right about now. In 2004, for instance, the first named storm didn't pop up until the last day of July.

"That was the same year that had Charlie, Frances, Ivan and Jeanne," Feltgen said. "We ended up with 15 named storms."

Think back to 1992, when the first tropical storm formed Aug. 17. In a week's time, it morphed into Hurricane Andrew and steamrolled across South Miami-Dade as the last Category 5 storm to hit the United States.

The levee system of New Orleans is designed to withstand a Category 3 storm surge. If Gustav intensifies more than the NHC forecast is calling for, there is a significant threat of multiple levee failures in the New Orleans levee system resulting in flooding of portions of the city. However, the latest 12Z (8 am EDT) model runs have shifted their landfall points a bit further west, reducing the odds of a Category 4 storm surge in New Orleans. My best guess is that New Orleans will suffer a Category 2 or 3-level storm surge. The levees will hold with that level of storm surge, if they perform as designed.

At 530 PM CDT, weakening Hurricane Dolly had slowed to a crawl and was centered over western Willacy County. The southwest side of the center continues to produce torrential rains which are quickly adding up from southern and southwestern Willacy County continuing into much of Cameron County, with heavy rains now heading into eastern Hidalgo and southeastern Brooks County. As the night wears on, the locally heavy rains will continue, with an additional 3 to 7 inches possible in these areas and the likelihood of 2 to 5 inches stretching into the western Lower Rio Grande Valley and Rio Grande Plains as Dolly weakens to a tropical storm but continues to spread heavy rains and gusty winds. Minor damage is still possible especially in eastern Hidalgo, Willacy, and Cameron County. Such damage will include more downed tree limbs, power lines, and minor structural damage. Extensive damage reports in Willacy, as well as across eastern Cameron County and especially from Port Isabel to South Padre Island, continue to trickle in. A brief summary of reports so far is listed below.

Considerable freshwater flooding may continue well into the night from eastern Hidalgo through Cameron County, with structures threatened in some areas along with potentially high waters in poor drainage areas with life threatening conditions possible! Residents are urged to remain indoors until conditions begin to improve sometime on Thursday. Significant flooding has been reported in Harlingen as of 530 PM. State Officials reported two feet of water in portions of downtown, with water in homes near Jackson Streeet. Police reported flooding on Polk, Taylor, Pierce, Filmore, and Commerce Streets. Meanwhile, streets in subdivisions on the north side of the city had up to six inches of water covering the ground. Estimated rainfall between 5 and up to 12 inches in Cameron County have caused widespread flooding of poor drainage areas from Brownsville to Port Isabel and South Padre Island. Numerous roads are covered in water, with poor drainage locations impassible.

Extensive damage reports continue to trickle in to the NWS office from South Padre Island. Dozens of roofs have been reported torn off of residences and businesses, and a large amount of debris was noted on roads. Included landmarks were the Radisson Resort, the Holiday Inn, and the Sea Ranch Restaurant. One person was reported sucked out of a doorway on a 7th floor condominium where he fell and was injured. Hundreds, if not thousands, of trees and limbs have been damaged throughout Cameron and Willacy Counties. Extensive property damage has also been reported along State Highway 186 between Raymondville and Port Mansfield, where the southwestern eyewall continued to wreak havoc. Stay tuned for updates later this evening.

...SEVERE FLOODING REPORTED IN HARLINGEN...

HEAVY AND PERSISTENT SHOWERS...ASSOCIATED WITH THE EYE OF WEAKENING HURRICANE DOLLY...ARE CAUSING MAJOR FLOODING IN THE CITY OF HARLINGEN THIS EVENING.

A TEXAS STATE OFFICIAL REPORTED TWO FEET OF WATER IN PORTIONS OF DOWNTOWN HARLINGEN...WITH WATER IN HOMES IN THE JACKSON STREET AREA. THE HARLINGEN POLICE DEPARTMENT REPORTED FLOODING ON POLK... TAYLOR...PIERCE...FILMORE...AND COMMERCE.

The crewmembers aboard the space station took a short break Saturday to get a look at the storm from their vantage point. Even from space, the storm expected to reach the Gulf of Mexico Aug. 21 and gain strength as a potential Cat 5 storm, impresses the crew with its size.

"We're eventually going to get a strong enough storm in a densely populated area to have a major disaster," he said. "I know people don't want to hear this, and I'm generally a very positive person, but we're setting ourselves up for this major disaster."

More than 1,300 deaths across the Gulf Coast were attributed to Hurricane Katrina, the worst human toll from a weather event in the United States since the 1920s.

But Mayfield warns that 10 times as many fatalities could occur in what he sees as an inevitable strike by a huge storm during the current highly active hurricane cycle, which is expected to last another 10 to 20 years.

His apocalyptic vision of thousands dead and millions homeless is a different side of the persona he established as head of the hurricane center.

What is lacking in the United States is the political will to make and impose hard decisions on building codes and land use in the face of resistance from the influential building industry and a public still willing to gamble that the big one will never hit, he said.

"It's good for the tax base" to allow developers to put up buildings on the coastline, Mayfield said in explaining politicians' reluctance to deter housing projects that expose residents to storm risks.

"I don't want the builders to get mad at me," he said, "but the building industry strongly opposes improvement in building codes."

Consumers also have yet to demand sturdier construction, Mayfield added. A builder gets a better return on investment in upgraded carpet and appliances than for safety features above and beyond most states' minimal requirements, he said.

Seven feet of seawater swamps Key Biscayne and 45 miles of coastline from Miami Beach to Deerfield Beach. Saltwater surges through some houses in Hollywood, Coconut Grove and elsewhere. Waist-deep freshwater blankets vast regions of suburban Broward and Miami-Dade counties.

Ferocious winds crush tens of thousands of roofs and gut numerous office buildings. Residents who defy orders to evacuate skyscrapers in Miami Beach, on Hollywood's beach and along Miami's downtown corridors could be blown out of their apartments. Power outages persist for months rather than weeks.

According to simulations conducted for The Miami Herald by scientists at the National Hurricane Center and interviews with a wide range of experts, those are not merely theoretical worst-case scenarios.

A new, unpublished research paper by Kerry Emanuel at the Massachusetts Institute of Technology torpedoes one of the few comforting thoughts of this storm-racked era: The notion that our current spree of active hurricane seasons is part of a natural cycle that's due to calm down in 10 or 20 years.

Instead, Emanuel says, the culprit is probably global warming.

As a result, "it's unlikely we'll ever see a quiet decade for the next 100 years in the Atlantic," said Emanuel, a professor of tropical meteorology and climate, and author of the respected 2005 hurricane text Divine Wind. "I don't think there's any evidence of anything you would call a cycle."

We still could see some calm years here and there, he said — maybe because of a periodic El Niño, which depresses Atlantic hurricanes.

The new paper, co-written with Penn State researcher Michael Mann, promises to stoke a debate Emanuel inspired last summer — when he published research tying global warming to an increase in hurricane strength in both the Atlantic and North Pacific since the 1970s.

In the 1970s, the average number of intense Category 4 and 5 hurricanes occurring globally was about 10 per year. Since 1990, that number has nearly doubled, averaging about 18 a year.

Category 4 hurricanes have sustained winds from 131 to 155 mph. Category 5 systems, such as Hurricane Katrina at its peak, feature winds of 156 mph or more. Last year, Wilma packed wind speeds of 175 mph and set a record as the strongest hurricane in terms of barometric pressure.

While some scientists believe this trend is just part of natural ocean and atmospheric cycles, others argue that rising sea surface temperatures as a side effect of global warming is the primary culprit.

According to this scenario, warming temperatures heat up the surface of the oceans, increasing evaporation and putting more water vapor into the atmosphere. This in turn provides added fuel for storms as they travel over open oceans.