In its 11 a.m. HST update, the Central Pacific Hurricane Center said the center of the storm was about 920 miles east of Hilo, with maximum sustained winds of 50 mph, and was moving west-northwest at 18 mph.
Tropical storm force winds extended about 150 miles from the center and Flossie was expected to follow its current track for the next 24 hours before taking a gradual turn toward the west and losing some forward speed Sunday.
The storm is expected to weaken during the next 48 hours. No coastal warnings or watches were in effect.
Flossie -- the sixth named storm of the Pacific hurricane season -- was expected to make landfall Sunday, the Honolulu Star Advertiser reported.
"Even though the water temperatures increase along the expected track of Flossie beginning in about 48 hours, westerly shear and a drier air mass should result in additional weakening," forecasters said.