Tropical Storm Helene: 5-day forecast track. NOAA/NHC graphic

By 5 pm EDT Thursday, Helene, the eighth tropical storm of the 2006 Atlantic hurricane season, had maximum sustained winds of 45 miles per hour, the US National Hurricane Center said.

The swirling mass of gusty thunderstorms was located around 885 miles west of the southernmost Cape Verde Islands and was moving west-northwest at 16 mph, the Miami-based center said in an advisory.

It was expected to strengthen in the coming days into a hurricane but would most likely start curving to the northwest well before approaching the US East Coast, computer models showed.

Gordon, meanwhile, the season's third hurricane and the first to become what meteorologists call a major storm with winds in excess of 111 mph, was located around 600 miles east of the British mid-Atlantic territory of Bermuda and moving northeast at 12 mph.

With winds of 120 mph, it was expected to keep well east of Bermuda, which was raked by Hurricane Florence on Monday, and start weakening over cooler waters.

While three hurricanes have formed in August and September, the 2006 season has been mild compared to 2005, when 28 named storms swept through the Atlantic and the Caribbean, 15 of which strengthened into hurricanes.

Hurricane Katrina devastated New Orleans just over a year ago and hurricanes Rita and Katrina were among the strongest Atlantic storms ever recorded.

Weather forecasters initially predicted that this year would also be more active than usual but have since cut their storm forecasts.

The US National Oceanic and Atmospheric Administration said on Wednesday that "El Nino" conditions had developed in the eastern Pacific.

El Nino, a warming of waters in the eastern Pacific, strengthens wind shear. Wind shear, a change of wind speed or direction at different altitudes, disrupts the formation of Atlantic hurricanes.