Fernanda, a powerful Category 4 hurricane in the Eastern Pacific, was expected to maintain its strength through the weekend, but then start weakening as it approaches the Central Pacific.

At 11 p.m. Hawaii time, Fernanda had maximum sustained winds around 145 mph and was about 2,296 miles southeast of Hilo, moving west at 12 mph. Hurricane-force winds extended just 30 miles from the storm’s center.

The forecast calls for Fernanda to continue moving westward to west-northwestward toward the Central Pacific.

“Some additional strengthening is possible tonight. After that, little change in strength is expected through Sunday,” said forecasters with the National Hurricane Center in Miami. A Category 4 hurricane has maximum sustained winds of 130 to 156 mph.

But Fernanda should start weakening early next week as it takes a northwesterly turn over cooler waters. On Wednesday, Fernanda is expected to be a strong tropical storm with maximum sustained winds of around 70 mph as it closes in on the Central Pacific.

It is still too far from Hawaii to know whether it will have a direct impact on the state’s weather later in the month.

Forecasters expect cooler waters and wind shear to weaken the storm as it moves northwest and approaches the Central Pacific.

“This is all subject to change,” National Weather Service in Honolulu forecaster Henry Lau warned Thursday night. “It still can maintain that intensity.”

When the storm crosses into the Central Pacific, the forecasters at the Central Pacific Hurricane Center on Oahu will take the lead in monitoring the storm. But Fernanda “is not forecast to enter our area of responsibility until next Thursday,” Lau said.