Hurricane Calvin continued strengthening overnight far from Hawaii in the East Pacific.

The storm is expected to weaken significantly before it approaches the islands next week but still could deliver heavy rain and wind.

At 11 p.m. Thursday, the National Hurricane Center in Miami reported that Calvin had sustained winds of 105 mph, making it a Category 2 storm. The hurricane was centered about 2,240 southeast of Hilo, and moving west at 16 mph. “A west to west-northwest motion is expected to continue during the next several days,” NHC forecasters said.

Hurricane-force winds extend outward 25 miles from Calvin’s center and tropical storm-force winds extend outward about 115 miles, they said.

“Some additional strengthening is forecast during the next day or so,” forecasters said last night. “Gradual weakening is expected to commence by the weekend as Calvin begins to move over cooler water and into a less-favorable surrounding environment.”

The five-day forecast has Calvin becoming a Category 3 hurricane today, with maximum sustained winds of 115 mph, before began its gradual weakening. It is expected to enter the Central Pacific early next week.

By the end of the five-day period late Tuesday, the storm is projected to be a post-tropical remnant low with winds of 35 mph as it approaches Hilo from the southeast.

The National Weather Service in Honolulu says Calvin will likely affect the state beginning Tuesday, “but it is too early for details.”