Hurricane Kristy restrengthened to a Category 5 storm on Thursday and fluctuations in strength are expected overnight with rapid weakening on Friday, the National Hurricane Center said Thursday afternoon.

As of Thursday afternoon, Kristy was about 970 miles southwest of the southern tip of Baja, California and continues to move west. The hurricane center said west to west-northwest motion is forecast through Thursday evening, with slower northwest to north-northwest motion expected late Friday.

Kristy had maximum sustained winds of nearly 160 mph with higher gusts Thursday afternoon, the NHC said. The storm is expected to weaken quickly from Thursday night or Friday.

The storm was expected to continue moving over open water, but the swell generated by Kristy will impact parts of the west coast of California’s Baja Peninsula late this week.k and this weekend the hurricane center said. These waves are “likely to create life-threatening surf and rip conditions,” they said.