Adrian strengthened to a major hurricane Thursday off the Pacific coast of Mexico, with sustained winds of 115 miles (185 kilometers) per hour but posing no immediate threat to land, the US National Hurricane Center said.

The first hurricane of the 2011 season, Adrian was a category three storm centered around 440 miles (710 kilometers) south-southeast of Cabo Corrientes, Mexico, and was moving northwest.

"This general motion is expected to continue during the next two days... keeping the hurricane away from the coast of Mexico," the NHC said in an update.

The Miami-based hurricane center said Adrian could strengthen Thursday or Friday but then weaken.

While the storm was not expected to hit land, the hurricane center said swells from Adrian "will continue to affect a portion of the southwestern Mexico coast" and "could cause life-threatening surf and rip currents."

The hurricane season, which started on June 1 and runs until November 30, will feature atmospheric conditions which experts predict will lead to formation of 12 to 18 named tropical storms in the Atlantic zone, of which six to 10 could become hurricanes, according to the US National Oceanic and Atmospheric Administration (NOAA).

NOAA forecasts an elevated threat this year to the United States and Caribbean nations, and predicts between three and six major storms of Category 3 intensity or higher on the five-level Saffir-Simpson hurricane wind scale.