SACRAMENTO, Calif. (CBS13/AP) — California’s improving coronavirus numbers continued their downward fall, leading to Tuesday’s announcement that much of the San Francisco Bay Area can reopen to a greater degree and that now 94% of the state’s population is out from under the most severe restrictions.

Yolo County has become the first area in the Greater Sacramento region to move into the Orange (moderate) COVID-19 alert tier.

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Several changes in tiers were announced on Tuesday, with a large part of the state now in less restrictive tiers of reopening.

One of the biggest changes, when a county reaches the Orange tier, is arguably to professional sports. According to state guidelines, outdoor sports venues can reopen to 20 percent capacity.

Restrictions on outdoor live events will also be relaxed after April 1, per state guidelines announced earlier in the month.

San Francisco Mayor London Breed and Director of Health Dr. Grant Colfax said the expanded activities can begin Wednesday. Breed credited swift vaccinations and ongoing safety precautions for the shift.

“This year has been so tough on so many — from our kids and families, to our small businesses and their employees — and this move to the orange tier and reopening more activities and businesses than we have since last March gives us all more hope for the future,” Breed said in a statement.

The three Bay Area counties had been among 42 counties in the red tier under California’s color-coded four-step process. That tier signals a “substantial” threat of spreading the virus. Purple is the most restrictive tier and indicates widespread transmission. Fresno is the only county among the state’s 10 most populous in that category.

Also moving to the moderate tier are Lassen, Trinity and Yolo counties, all in Northern California.

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Sierra County joined similarly isolated Alpine County in the least restrictive yellow tier with minimal virus transmission and restrictions. Gov. Gavin Newsom recently said the state is developing a new “green tier” that would end many restrictions altogether.

It’s likely that within a few weeks Los Angeles, San Diego and much of the rest of the state will be in the lowest two tiers.

The changes come as California continues to see dramatic improvements since the deadliest surge started in late fall and peaked in early January. The state’s seven-day positive rate for tests now is just 1.7% while a robust 30% of intensive care unit beds are available.

During the darkest days of the pandemic, hospitals in Los Angeles and other locations ran out of usual ICU beds and in some cases set up tents in parking lots to triage patients.

California’s Central Valley, where most of the country’s fruits and vegetables are grown, has seen marked improvement in the last two months but continues to lag other regions. Still, progress is being made. Stanislaus County and Kern County, the second-most populous in the San Joaquin Valley, moved out of the most restrictive tier.

Stanislaus County’s public health officer, Dr. Julie Vaishampayan, warned residents not to become lax on safety precautions because “we could easily slip back into purple tier if we do not stay vigilant.”

California is also moving closer to its self-imposed threshold of getting 4 million vaccine doses into low-income communities. The state recently tied reopening to ensuring those populations are vaccinated and once that “equity” mark is reached all counties can more quickly move out of the most restrictive tiers.

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The state says it has now administered nearly 3 million doses in those communities and more than 15 million statewide.