The state is currently conducting an average of 125,000 tests per day, and the number of contact tracers in California has grown to nearly 11,000.
California's Health and Human Services Secretary Dr. Mark Ghaly said 90% of health departments across the state are getting results to people who've tested positive for COVID-19 within 24 to 48 hours.
Meanwhile, contact tracers are contacting 95% of positive patients' contacts on the same day the person gets their test results, Ghaly added.
Newsom said the state is still working to increase testing efforts, while also helping those who may find it hard to isolate, like farmworkers and the homeless.
California's case rate remained stable, and the state's positivity rate was 2.6% as of Monday. However, Newsom continued to warn people of the virus especially as the holiday and flu season nears.
Newsom said he expected more counties to move to less restrictive tiers on Tuesday, but added that some counties are "teetering" between tiers.
RELATED: Map shows which counties can, can't reopen under Newsom's new 4-tier system
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The governor also provided an update on the ongoing wildfires that have scorched more than four million acres of California.
Firefighters were able to increase containment on some of the largest wildfires burning in the state
Firefighters are battling 14 major wildfires across the state, and containment has increased on some of the largest currently burning including:
Newsom said California is headed into another week of warm weather with temperatures expected to near record-highs in the Central Valley later this week.
PG&E is warning of a possible Public Safety Power Shutoff for more Bay area counties and the Sierra Nevada foothills as a wind event, and dry conditions heighten fire risk.