The teams were withdrawn from the field in Nashville after 15 minutes due to lightning but the one-and-a-half hour delay did little to change the momentum as the United States continued to dictate when play resumed.
The United States doubled their lead after 52 minutes when Jamaica goalkeeper Andre Blake could only parry Jordan Morris’s shot and Pulisic pounced on the loose ball to score.
Shamar Nicholson headed Jamaica back into contention in 69 minutes, the goal the first the United States have conceded at the tournament, but Man of the Match Pulisic restored the hosts' two-goal cushion three minutes from time when he was once again alert to a rebound from a Paul Arriola shot.
U.S. coach Gregg Berhalter said his side were not put out of their stride by the weather delay.
"It’s part of soccer and the guys dealt with it in a really good way," he said. "It gave us time to look at film and give them encouragement ... We showed a relentless spirit when we came back out tonight."
Jamaica's Blake said his team had given their all.
"The guys did a great job tonight, unfortunately the result didn’t go our way," he added. "I think this is probably our best game all tournament, that happens sometimes."
The defending champions will now play arch rivals Mexico in Sunday’s final at Soldier Field in Chicago.
The two have met in the Gold Cup final five times, with Mexico victorious all but once -- in 2007 when the United States won 2-1, also at Soldier Field.
(Reporting by Andrew Downie; Editing by Peter Rutherford)
