MIAMI (Reuters) - The first hurricane of the 2008 Atlantic storm season formed on Monday, hundreds of miles (km) away from the United States and the Caribbean islands, the U.S. National Hurricane Center said.
The Miami-based center said it was still too early to determine if Bertha would hit any land as computer models showed it would eventually start curving to the northwest and then to the north, possibly taking it near Bermuda.
Long-range storm track predictions are unreliable, however, and the hurricane center noted, "It is still not guaranteed that Bertha will recurve."
By 4:54 a.m. EDT, Hurricane Bertha was about 845 miles east of the northern Leeward Islands of the Caribbean and was moving toward the west-northwest at 17 miles per hour (28 km per hour).
The storm's top winds had reached near 75 mph (120 kph), just over the threshold at which tropical storms become hurricanes.
The hurricane center said some additional strengthening was expected during the next couple of days but it did not forecast Bertha to become stronger than a minimal Category 1 hurricane on the five-step Saffir-Simpson scale of hurricane intensity.
Energy markets have paid close attention to storms in the Atlantic since the devastating 2004 and 2005 hurricane seasons, during which a number of powerful hurricanes ripped through the Gulf of Mexico, toppling oil rigs and severing pipelines.
None of the computer models used to predict storm tracks indicated Bertha could steer south, into the Caribbean or toward the Gulf.
Hurricane forecasters have predicted this season, which began on June 1, will be average or above average. An average season has around 10 tropical storms, of which six reach hurricane strength with winds of at least 74 mph (119 kph).
The record 2005 season, which included Katrina, the hurricane that swamped New Orleans and killed 1,500 people on the U.S. Gulf Coast, saw 28 storms form.
Bertha formed last Thursday near the Cape Verde islands off Africa. It is unusual for storms to form so far east so early in the season, and when it does happen, it is frequently a harbinger of heightened storm activity.
More information about the hurricane is available at the National Hurricane Center's Web site (http://www.nhc.noaa.gov/#BERTHA).
(Reporting by Michael Christie, additional reporting by Stacey Joyce, Editing by Eric Beech)