MIAMI — U.S. government forecasters announced today they expect three to six major hurricanes from an above average Atlantic storm season.

No major hurricane has made a U.S. landfall in five years.

As many as 18 named tropical storms may develop during the six-month Atlantic hurricane season that begins June 1, according to forecasters at the National Ocean and Atmospheric Administration. Six to 10 of those storms could strengthen into hurricanes with top winds of at least 74 mph, the agency said. Three to six could become major hurricanes, with maximum winds of 111 mph and up.

Last year’s hurricane season was one of the busiest on record with 19 named storms, including 12 hurricanes. The 2011 season was not expected to be as extreme, partly because ocean temperatures were only two degrees warmer than normal, instead of four degrees warmer as they were last year, said NOAA administrator Jane Lubchenco.

“We still expect that to support an above average hurricane season,” Lubchenco said.

Also, a Pacific Ocean weather phenomenon known as “La Nina” was expected to dissipate early in the summer before the season’s peak, typically from August to October, Lubchenco said.