The 28-year old striker is expected to be officially unveiled by the Quakes this week and returns to MLS after two years in Israel with Maccabi Tel Aviv and Bnei Sakhnin FC.
Sealy's addition to the Quakes squad is a major boost according to general manager John Doyle.
"Scott would add a lot of depth to our team," general manager John Doyle said. "He's a proven goal scorer. We never wanted Scott to leave."
Sealy commenced his professional career with the Kansas City Wizards in 2005 before moving onto San Jose in 2008. When he left for Israel, the club retained his MLS rights and have been able to pick him up as a free agent.