Newsom made the announcement during a Friday press conference. The order would currently disqualify all schools in Fresno, Kings, Tulare, Merced and Madera counties, unless the counties are able to get off the watch list for 14 days.
All school staff and students in the third grade or higher must wear a mask to school. Younger students are encouraged to wear masks or face shields, and schools must practice physical distancing and conduct regular testing and contact tracing.
If a school district meets the criteria and is allowed to open, they would be forced to close if more than 5% of the school tests positive for COVID-19. Additionally, if more than 25% of schools in a district are forced to close, the entire district must go back to distance learning.
Schools will also be required to provide robust distance learning programs and ensure all students have access to devices and internet connectivity.
Previously, the governor and the State Superintendent of Public Instruction, Tony Thurmond, have both said that the decision would be left entirely to local school districts.
Many of the larger school districts across the state, including in San Francisco, Los Angeles and San Diego, have already announced they're starting fall instruction exclusively online.
Locally, the decision to have students return to campus for in-person instruction has been mixed. Central Unified School District and Selma Unified opted to start the new year virtually in the fall. Meanwhile, the Clovis Unified Board of Trustees voted to have their students start classes on campus. However, those districts would fall under the state's new guidelines unless the counties are able to get off the coronavirus watch list.
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Superintendent Thurmond expressed support for the districts who have decided to continue distance learning in a virtual press conference Wednesday.
"I think that if school opened tomorrow, most of our districts would open in distance learning," Thurmond said. "And that is a decision that I think is a good decision if conditions don't change right now."
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"Since we've issued our guidance, conditions have changed dramatically," said Thurmond, referencing the 62 pages of reopening guidelines issued by the California Department of Education last month. "We know that in many communities throughout our state we're seeing high rates of infection in the community."
California is in the middle of a summer surge in coronavirus cases and hospitalizations, and on Monday, Gov. Newsom announced rollbacks on the state's reopening plan.
Bars, both indoor and outdoor, have been ordered to close down statewide. Restaurants are being told to cease indoor operations. Outdoor dining and takeout are still allowed.
All counties also have to close indoor operations at wineries, tasting rooms, movie theaters, family entertainment centers, zoos, museums and card rooms.
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Counties who have been on the California's monitoring list for worsening coronavirus cases were also ordered to close their gyms, hair salons, worship services, and malls. The list includes Fresno, Kings, Tulare, Merced and Madera counties.
ABC7 News' Alix Martichoux and Amy Hollyfield contributed to this report.
For more news coverage on the coronavirus and COVID-19 go to ABC30.com/coronavirus