Coming at you. Toyota will be building the newly updated Lexus ES at its Georgetown, Kentucky plant.

Toyota Motor Co. is expected to announce Friday plans to invest more than $500 million in its Georgetown, Kentucky plant to move production of one of its Lexus luxury vehicles to the U.S. for the first time.

The world’s largest automaker already produces more than half of the vehicles it sells in the U.S. at various North American assembly plants. But it has, until now, limited production of its Lexus line almost exclusively to Japanese factories.  Though the RX crossover is now produced in Canada, the Lexus ES will become the first luxury model – and the 11^th Toyota vehicle assembled in the U.S.

Toyota is the last of the Japanese “Big Three” to move at least some luxury car production to the States. But like rivals Honda Motor Co. and Nissan Motor Co., it has been hollowing out production in the home Japanese market due to concerns about exchange rates – as well as potential production issues underscored by the March 2011 Japanese earthquake and tsunami that all but shut down the maker’s operations for much of the following nine months.

According to a spokesperson, “Everything out there is speculation,” with the details of what Toyota describes as a “production announcement” set to be released during a Friday morning news conference. Signifying the importance of that event, the news will be announced by Toyota President Akio Toyoda – grandson of the automaker’s founder – and Jim Lentz, CEO of Toyota’s North American region.

On Wednesday, Kentucky officials provided a hint of what will be said when the Kentucky Economic Development Authority confirmed it would provide Toyota with $146.5 million in tax incentives to expand the Georgetown plant and add a new model.

Toyota, in turn, will be required to invest $531 million and add 570 jobs. The expansion is expected to boost capacity at Georgetown, which already builds the popular Camry sedan, by 50,000 units annually. Production of the Lexus ES sedan is set to begin in 2015, according to sources.

The announcement comes after Toyoda, Lentz and nearly 70 other executives and managers flew into Washington, D.C. for what the Detroit News Washington Bureau described as a “fly-in.”  Along with leaders on Capitol Hill, senior Toyota executives met with representatives of the Obama White House. The meetings came just days after the administration’s decision to allow Japan to participate in the Asia/Pacific trade talks.

That has generated stiff opposition from some in Detroit’s automotive industry, especially in the wake of the recent, steep decline of the Japanese yen – a move Ford Motor Co. officials have described as inappropriate Japanese government meddling meant to improve the competitiveness of the country’s automakers.

Despite the shift in exchange rates, however, few expect to see a reversal in the ongoing trend by Japanese makers to continue moving production overseas. Nissan CEO Carlos Ghosn said late last month that he does not want to risk the possibility that the yen might again appreciate to the point where Japanese-made cars can no longer be cost-competitive.

Toyota has been the most reluctant to shift production, positioning itself as a defender of the Japanese economy. But it has been increasingly worried about home market production, as well, and the decision to move the Lexus ES to Kentucky suggests further shifts are possible. In particular, most industry analysts anticipate the popular Toyota Prius will eventually be produced somewhere in North America, as well.

Even before the new move, Toyota had invested about $18 billion in its various U.S. operations, including 10 assembly plants, design facilities, research-and-development centers and test tracks. It claims to have 30,000 direct U.S. employees and to indirectly employ 365,000 Americans all told.