California Gov. Gavin Newsom expects about 56% of the state's population – more than 22 million Californians – to be infected with the coronavirus over an eight-week period.
The estimate was in a letter Newsom sent to President Trump, dated Wednesday, asking Trump to deploy the naval hospital ship Mercy to the waters off of Los Angeles through the beginning of September.
Newsom wrote that the ship would help "decompress" the health care delivery system during the anticipated crisis.
"Our state and health care delivery system are significantly impacted by the rapid rise of COVID-19 cases," the letter said.
The letter, made public by Newsom's office on Thursday, said the case rate was doubling every four days in some parts of the most populous U.S. state.
As of Thursday, California had 675 confirmed cases of COVID-19, according to the California Department of Public Health.