SAN FRANCISCO (CBS SF) — Health officials in San Francisco on Wednesday afternoon warned of an alarming spike in the city’s coronavirus hospitalization rate this week.

While the new case rate for San Francisco remained relatively low at just under six new cases per 100,000 residents in the city — the equivalent of about 52 new cases total each day — the rate of weekly change in hospitalizations shot up 57 percent in the past three days

READ MORE: UPDATE: Atmospheric River Crashes Onshore; Flood Warning Issued For Napa, Sonoma Counties

“We are seeing increased cases and increased rates of hospitalizations due to COVID. Our indicators are sensitive to the changes that will impact our community,” a tweet posted to the San Francisco Department of Public Health account read.

READ MORE: UPDATE: Streets Flood in San Rafael, Mill Valley as Wild Storm Lashes Bay Area

San Francisco Mayor London Breed also tweeted out a word of caution, referencing Governor Gavin Newsom’s announcement earlier in the day to be careful during the July 4th holiday.

MORE NEWS: Stephen Curry Reaches 5,000 Assists, Warriors Beat Kings 119-107

“Cases & hospitalizations have gone up. Avoid crowds. Don’t gather with people you don’t live with this weekend,” the mayor said.