The 32-year-old, who claimed Mistral bronze at Athens 2004 and RS:X silver at London 2012, has spent the past three weeks training at the Brazilian venue.
Dempsey has a fine pedigree at World Championships having most notably won his maiden title in 2009 and silver in 2012 while his first outing of 2013 also saw him climb the podium.
He claimed silver amid an experimental race formation at the opening World Cup of the year in Miami in January, his first event since the London 2012 Olympics.
Dempsey will be joined in Brazil by Elliot Carney and Tom Squires in the men's fleet and Bryony Shaw, who won RS:X bronze at the Beijing 2008 Olympics, and Izzy Hamilton in the women's fleet.
And he can't wait to get stuck in in Buzios as he continues the long road to the next Olympics in Rio de Janeiro in 2016.
"It will be difficult to win the worlds, but not impossible," said Dempsey. "It's likely to be very windy and we aren't expecting a range of conditions, but you always find something extra at a worlds.
"Right now it's just about being out on my board again and really starting to look ahead at what the next three-and-a-half years can bring."