From a story on axios.com by Andrew Freedman headlined “Hurricane Lee churns west as a powerful Category 4 storm”:

Hurricane Lee “skyrocketed” in intensity on Thursday and strengthened into a Category 5 storm just before 11pm ET, before weakening slightly to a Category 4 storm Friday morning, per the National Hurricane Center.

The big picture: The powerful hurricane is forecast to move well north of the Leeward Islands and Puerto Rico, and may slow down east-northeast of the Bahamas this weekend.

The NHC found the storm made an exceptional intensity leap of 80 mph in 24 hours. The escalation greatly exceeds the 35 mph increase needed to fit the definition of rapid intensification.