Danielle, the first major hurricane of the season, was located some 545 miles (875 km) southeast of Bermuda and was moving northwest at 12 miles per hour (19 km per hour).

It had top sustained winds of 135 mph (215 kph). Any storm packing winds of at least 111 mph (178 kph) is ranked as "major" by the Miami-based hurricane center.

Computer models show Danielle tracking northwest and then in a more northerly direction before passing well east of Bermuda on Saturday night.

The Hurricane Center said Bermuda would experience large waves and dangerous surf conditions over the next few days before the swells reach the US East Coast where they are likely to cause dangerous rip currents this weekend.

Danielle is expected to strengthen within the next 36 hours before weakening.

In the Pacific, Hurricane Frank, the third Pacific hurricane of the season, formed this week but eventually veered away from Mexico and out to sea. It was expected to weaken as it moved over cooler waters.

The Atlantic season's first hurricane was Alex, which churned ashore on the Mexico-Texas border as a Category 2 storm on June 30.

Weather analysts forecast this year's storm season to be particularly active, but so far there have been fewer storms than expected.