The system, just north of the Virgin Islands, has an 80 percent chance of becoming tropical in the next five days, according to the U.S. National Hurricane Center in Miami.
If the system becomes better organized and its winds reach 39 miles (63 kilometers) per hour, it will become the third named storm of the Atlantic hurricane season that runs from June 1 to Nov. 30.
While the high mountains of Hispaniola, home to Haiti and the Dominican Republic, may keep the storm from forming overnight, by tomorrow it will be nearing the southeastern Bahamas, where conditions will improve, the hurricane center said in an outlook today.
“Regardless of tropical cyclone formation, gusty winds and heavy rainfall are expected across portions of the Leeward Islands, Puerto Rico and the Virgin Islands today, and over Hispaniola and the southeastern Bahamas tonight and Saturday,” the center said.
A tropical cyclone is the scientific name for the class of systems that range from tropical depressions to hurricanes.
Kottlowski said as the storm moves toward the Bahamas, wind shear will decline. Shear is the name given to winds that blow at different speeds or directions at different altitudes. It can tear at the structure of a storm.
The most likely path for any storm that forms will be north parallel to the U.S. East Coast, then east into the North Atlantic, Kottlowski said. The system would probably be south of Nova Scotia and passing Newfoundland by the U.S. Labor Day weekend holiday.
One computer model suggests that the prevailing weather pattern forecasters believe will drag the system north may instead leave it behind, Kottlowski said. If that happens, the storm may drift into North Carolina or Virginia sometime on Aug. 27, he said.
“Is it likely? No, but you always have to respect these outlying models,” Kottlowski said by telephone.
As the forecasters watch for the development of Cristobal in the Atlantic, three systems are churning in the eastern Pacific.
Kottlowski said tropical storms Karina, Lowell and Marie aren’t a threat to land.
Marie may grow into a major hurricane, with winds of at least 111 mph. However, it will remain far off Mexico’s Pacific coast, he said.
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