Massachusetts Governor Charlie Baker unveiled a new tool in the fight against COVID-19 Tuesday: a statewide mapthat identifies communities in which the disease is still spreading, and other communities in which it’s largely contained.

Higher-risk communities, with an average daily COVID case rate of more than 8 per 100,000 residents, will be identified with the color red. Moderate-risk communities, with an average of between 4 and 8 cases per 100,000 residents, will be colored yellow.

“These communities require specific strategies to attack COVID there," Baker said, and the state will "work with them to stop the spread.”

“Every community is different,” he added. “But this could include additional testing, tracing, and isolation resources, and we’re also implementing stepped up enforcement measures … We’ll also work with these communities on messaging and other communication strategies as we and they see fit.”

Four communities in Eastern Massachusetts — Chelsea, Everett, Lynn, and Revere — are currently designed red, or high risk, with about 30 more meeting the criteria for a yellow or moderate-risk designation.

Communities with less than 4 cases will be marked green, and the lowest-risk cities and towns — with less than five cases overall reported in the past two weeks — will be left white.

The map will be updated weekly.

At present, Baker noted, 318 of Massachusetts’ 351 cities and towns are lower risk.

“The good news is, the vast majority of the communities in Massachusetts are experiencing low COVID case numbers, and most are seeing trends that are moving in the right direction,” he said.

The governor was quick with a caveat, however.

“Regardless of where your community sits, COVID is not going away,” he said. “Your actions, no matter where you live or where you work, will determine, in many respects, whether and how this virus spreads.”

Baker said he and Lieutenant Governor Karen Polito have already contacted the leaders of higher- and moderate-risk communities, to “start a dialog” on how the state can support their anti-COVID efforts. As those discussions progress, he has some preliminary advice for the residents of those cities and towns.

“Start with the … assumption that you need to do all you can to keep your family and yourselves safe,” he said. “Wear a mask if you go out. Wash your hands. Engage in the basic hygiene strategies that we’ve all talked about for months.

“Avoid large-group gatherings,” Baker added. “And while it may be difficult, find a way to be a little less familiar with the people with whom you are most familiar outside your family."

In response to a reporter’s question, Baker said cities and towns designated as lower risk should take that assessment into account as they formulate plans for how students will return to school this fall.

“We would certainly hope that based on this data, if you’re in a green or a white community, I can’t imagine a good reason not to go back [to in-person learning], whether it’s full time or in some sort of a hybrid,” Baker said. “Because for all intents and purposes, you meet all the benchmarks that are being used across the country and across New England to make decisions about whether it’s safe to go back to school.”

Baker’s heightened focus on higher-risk communities comes as the state implements new guidelines aimed at curbing COVID’s spread, including reducing the limit on outdoor gatherings from 100 people to 50 and requiring masks when more than 10 people from separate households congregate.

After repeatedly expressing frustration at some people’s willingness to engage in unsafe behavior, Baker also recently announced the creation of a new cross-agency COVID Enforcement and Intervention Team.

On Tuesday, Baker said that new entity will prioritize compliance, not punishment.

“The idea here is not to be issuing big fines,” Baker said. “The idea here is to either make sure people are abiding by the gathering rules and the guidance, or … to send people home if they’re not.

“Because we’re not doing anybody any good, with respect to the public-health issues we’re talking about here, if we let these folks just continue to do this sort of thing … It’s clearly having an impact, and the impact it’s having is negative.”

Due to concerns over rising infections in the state, Baker last week postponed indefinitely the next stage of the state's economic reopening plan.