00:56 Atlantic Hurricane Season Goes Greek For only the second time ever, the National Hurricane Center has run out of names, so they've turned to the Greek alphabet.

At a Glance The tropical system was responsible for six deaths Monday in the Dominican Republic.

Three others may have been killed by conditions from the storm, but authorities are still investigating.

Preparations are already underway in Jamaica and the Cayman Islands, where the storm is expected to hit later this week.

Officials in Jamaica and the Cayman Islands are warning residents to be prepared for heavy rains and strong winds as a tropical system that killed at least six people in the Dominican Republic moves further west.

The six deaths and 12 injuries occurred Sunday aboard a bus filled with people returning from a beach excursion near the town of Nagua in the northeastern part of the country, the AP said. The storm brought power lines down onto the bus, sparking a deadly fire, Metropolitan Transportation Authority spokesman Diego Pesqueira said in the report.

Not far from Nagua, three bodies were recovered and four others remained missing after a tour boat overturned Sunday off the Samana Peninsula, the AP also reported. The cause of the incident has yet to be determined, military spokesman Arsenio Maldonado told the AP, but there was a small craft advisory due to the storm at the time the boat flipped.

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In Jamaica, events have been canceled and store owners have been asked to open their businesses so citizens can purchase emergency supplies , according to the Jamaica Gleaner. The nation's government activated the National Emergency Center, and residents in coastal and low-lying areas were instructed to move to higher ground once the storm approaches, the report added.

"We are going to be in for a rough two to three days," local government minister Desmond McKenzie told the Jamaica Gleaner.

All small craft operators, including fishers from the cays and banks, are reminded to remain in safe harbor until all warning messages have been lifted and wind and sea conditions return to normal.

The Cayman Islands Joint Marine Unit also issued a warning Monday, saying boaters should stay off the water while the system passes through the area.

Simon Boxall, with Cayman Islands Hazard Management, told the Cayman Compass he does not anticipate opening hurricane shelters for this storm, but that could change if the forecast gets worse.

“We don’t expect this will have a significant impact on us,” he said, but it could lead to high winds and localized flooding. “We’re not too anxious about it, but we are watching it closely."

A reconnaissance aircraft was scheduled to fly into the storm Monday evening, but had to return home before it could survey the system. The National Hurricane Center blamed a mechanical problem for the canceled mission. A second airplane was dispatched on Tuesday.

Forecasters expect the tropical system to strengthen in the coming days and become Tropical Storm Earl before moving toward Central America later this week.

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