Heavy rain showers over the Dominican Republic, Haiti and Puerto Rico are less likely to strengthen into a depression or tropical storm, the National Hurricane Center said.

The system has a 60 percent chance of developing into a stronger storm within two days, the center said in an advisory on its website at about 7:45 a.m. Miami time. That’s less likely than the center’s 70 percent probability from six hours earlier.

“A tropical depression is not expected to form today but environmental conditions are still favorable for some development,” the center said. “Heavy rains could cause life- threatening flash floods and mudslides in mountainous areas.”

Photo: Satellite image of the Caribbean. Photo courtesy of the National Hurricane Center.

The downpours will affect the Virgin Islands, Puerto Rico, the Dominican Republic and Haiti today and the Bahamas over the next two days, the center said. The system is moving west- northwest at about 10 miles (16 kilometers) an hour. If it keeps that track, the storm would be on a course that may take it over the Gulf of Mexico oil slick.

Some models show the storm developing into a Category 1 hurricane by the weekend, Jim Rouiller, a senior energy meteorologist at Planalytics Inc. in Pennsylvania, said yesterday. That’s the lowest category on the 5-step Saffir- Simpson scale of intensity. If the storm manages to form, it could come ashore in south Florida in about three days, said Allan Huffman, a meteorologist for AirDat LLC in North Carolina, which installs weather- gathering sensors on commercial aircraft.

“Most of the models show it at tropical storm strength as it approaches south Florida,” Huffman said yesterday by phone.

A tropical system entering the Gulf has the potential to drive the oil from the BP Plc spill, the worst in U.S. history, into the coast of Louisiana and Mississippi or disperse it over a wider area of water, according to the center.

According to an 8am update from the National Hurricane Center, “Early morning satellite images indicate that the shower activity associated with the tropical wave moving across Hispaniola has become less organized.”

Although the report states that a tropical depression is not expected to form today, conditions are still favorable for worsening as the system moves toward the west-northwest at about 10 mph away from Hispaniola into The Bahamas on Thursday.

“There is a high chance...60 percent...of this system becoming a tropical cyclone during the next 48 hours.”

Click here to read more at the National Hurricane Center

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