The U.S. dollar index is already up more than 7 percent year-to-date, but according to one currency expert, the rally is just getting started.
"I think that the Fed tightening story is the main one that is going to continue to drive the dollar." Lien added that blowout pending home sales and improving economic data will support a September rate hike.
"At the end of the day, data is improving and the language from the Federal Reserve is very consistent. They are going to raise interest rates," said Lien, managing director at BK Asset Management. "So I do think the greenback moves higher." Although she added that she expects the rally to lose steam post-hike.