When will Bay Area counties move out of the purple tier?

It has been more than three weeks since California Gov. Gavin Newsom lifted the regional stay at home order, allowing Bay Area counties to reopen several business sectors including outdoor dining and some indoor personal services such as haircuts.

When the order ended on Jan. 25, all nine counties in the region moved into the purple tier in the governor's color-coded reopening framework — and they have remained in this most-strict zone ever since. Throughout the state, most counties are in the purple with a few exceptions in remote counties including Del Norte (red), Trinity (orange), Plumas (red), Alpine (orange), Sierra (orange) and Mariposa (red).

The governor said in a press briefing Tuesday that Plumas County moved from purple to red this week, and he anticipates a substantial number of counties will also move to less-stringent tiers next week and in the weeks beyond if cases continue to decline.

"We'll see counties move, not just from purple to red, but more and more red to orange, and I anticipate based on the number that are already in orange, you'll see many more in that yellow tier as well, which is the most permissive of the tiers we put out 24 weeks ago in our blueprint for a safer reopening," Newsom said.

The state has seen a recent decline in cases and hospitalizations after the pandemic reached its all-time high in December and January. Newsom noted that a month ago the seven-day positivity rate (the percentage of people who test positive for the virus of all of individuals who are tested) in the state stood at 11.4%. On Tuesday, it was 3.5%.

The state's system sorts counties into four tiers — "purple" (widespread), "red" (substantial), "orange" (moderate) or "yellow" (minimal) — that measure the spread of COVID-19 and dictate what types of businesses and activities are allowed to open. The structure allows counties to be more restrictive and move more slowly than the state in reopening, if they wish.

A county's tier assignment is based on three metrics: the adjusted case rate (number of new cases per 100,000 residents, adjusted based on testing volume); the positivity rate (percentage of people who test positive for the virus of all individuals who are tested); and a health equity metric. The health equity metric only comes into play to help a county move to a less restrictive tier.

Counties in the purple category are reporting more than seven new daily cases per 100,000 residents and have positivity rates above 8%. For a county to move into the red tier, it must report an average of four to seven daily cases per 100,000 residents and a test positivity of 5% to 8% for 14 consecutive days. The orange tier requires one to 3.9 cases per 100,000 and a test positivity of 2% to 4.9%, and the yellow less than one case per 100,000 and lower than 2% positivity.

When a county jumps from the purple to the red tier, it can opt to increase retail capacity and allow several sectors to open indoors with modifications and capacity limits including museums, zoos, aquariums, gyms, movie theaters, restaurants and places of worship.

While elementary schools can operate with in-person learning in the purple tier, high schools and middle schools can also open in the red.

Where do Bay Area counties stand? Here's a look at the metrics posted by the state.

Alameda

16.4 new COVID cases per 100,000

12.6 adjusted case rate for the tier assignment

3.6% positivity (seven-day average)

Contra Costa

18.2 new COVID cases per 100,000

16.4 adjusted case rate for the tier assignment

7.3% positivity (seven-day average)

Marin

11.9 new COVID cases per 100,000

8.9 adjusted case rate for the tier assignment

2.4% positivity (seven-day average)

Napa

18.6 new COVID cases per 100,000

14.2 adjusted case rate for the tier assignment

4.6% positivity (seven-day average)

San Francisco

14.7 new COVID cases per 100,000

8.9 adjusted case rate for the tier assignment

2.6% positivity (seven-day average)

San Mateo

19.3 new COVID cases per 100,000

9.6 adjusted case rate for the tier assignment

2.8% positivity (seven-day average)

Santa Clara

17.7 new COVID cases per 100,000

10.9 adjusted case rate for the tier assignment

3.2% positivity (seven-day average)

Solano

19.2 new COVID cases per 100,000

18.4 adjusted case rate for the tier assignment

5.3% positivity (seven-day average)

Sonoma

15.3 new COVID cases per 100,000

13.8 adjusted case rate for the tier assignment

4% positivity (seven-day average)

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