The streets of the Seaport District in South Boston will be the venue for the Grand Prix of Boston — the Verizon IndyCar Series’ season-finale race — in 2016 and possibly subsequent years.

Organizers are set to announce the deal for the Labor Day weekend auto race tomorrow.

“The hope is that this will be an annual event in the city of Boston,” Grand Prix of Boston spokeswoman Kate Norton said.

The Verizon IndyCar Series is IndyCar’s premier open-wheel auto racing series. All races are broadcast on national TV networks.

As the Herald first reported last August, Mayor Martin J. Walsh sent a letter to IndyCar CEO Mark Miles last June, expressing interest in hosting the race as part of broader plans to attract high-profile events to Boston.

Boston organizers led by Mark Perrone, a former IndyCar executive from Ipswich, plan a temporary, modular street course track. Pre-race practice and IndyCar qualifying runs would be held throughout the weekend, with the main race on Sunday.

Other race-related weekend events under consideration include IndyCar driver autograph sessions and meet-and-greets, street festivals, car shows, a black-tie charity gala and a foot race on the car racetrack.

The events are expected to attract more than 250,000 spectators and have an annual economic impact of $75 million to $80 million, according to organizers.

It’s huge news for Boston’s visitor industry and economy, said a Hub tourism observer. “Labor Day is pretty much a quiet time of the year in the Boston-Cambridge area,” he said. “The biggest thing we have is kids coming back to … the colleges.”