Passengers wear face masks to protect against the COVID-19 (Coronavirus) after arriving at the LAX airport in Los Angeles, California on March 5, 2020.

"In the last 24 hours, we had 126 new COVID-19 cases, a 21 percent increase. In some parts of our state, our case rate is doubling every four days," Newsom wrote in a letter dated Wednesday . Newsom asked Trump to dispatch the USNS Mercy Hospital Ship to the Port of Los Angeles through Sept. 1 to help with the influx of expected cases.

California estimates that more than half of the state — 25.5 million people — will get the new coronavirus over the next eight weeks, according to a letter sent by Gov. Gavin Newsom to U.S. President Donald Trump.

The state reported nearly 699 confirmed cases as of 9 p.m. ET Wednesday night, according to the California health department. Newsom said the virus is spreading in the community in 23 counties across the state. It is the third hardest hit state in the U.S., behind Washington state which has 1,376 cases as of 6 p.m. EDT Thursday and New York which has at least 5,000 cases.

Earlier this week, Newsom ordered all non-essential businesses to close, including bars, beer pubs and wineries. Grocery stores, pharmacies, banks, cannabis clubs and other businesses deemed as essential are still open, state and local officials say.

San Francisco Bay area officials ordered some 7 million residents to "shelter in place" on Monday, prohibiting people from leaving their homes, except under "limited circumstances," according to the order.

People who venture out are expected to remain six feet apart, wash their hands, cover their coughs or sneezes and abide by a number of other restrictions. Non-essential businesses across the state, including wineries and bars, will be closed. But essential services such as grocery stores, banks and pharmacies will remain open.

Residents are allowed to walk their dogs or go for a run, so long as they maintain a distance of at least six feet from anyone they don't currently live with, San Francisco health officer Dr. Grant Colfax said at a press conference Monday.