Fed chair Jerome Powell will deliver remarks at Jackson Hole on Friday. State Street's chief strategist lays out what investors should listen for.

Jerome Powell’s speech at the Federal Reserve’s August summit in Jackson Hole, Wyoming, is always a high-stakes moment. This year, the central bank’s chair takes the podium under fire – facing fierce attacks from US President Donald Trump and a growing insurgency within his own institution.

Financial markets are taking in a collective breath ahead of Jerome Powell's eighth and final keynote Jackson Hole speech as Federal Reserve Chair. If the moves following his last seven are any guide,