Let's get the basics out of the way: the Fed will announce its latest interest-rate decision at 2 p.m. Eastern, alongside the latest summary of economic projections (i.e., the dot plot). That will be followed by a press conference with Fed Chair Jerome Powell at 2:30 p.m.

Wall Street is holding near its records after the Federal Reserve kicked off its efforts to prevent a recession with a bigger-than-usual cut to interest rates.

"This would be the third time that stocks entered a cycle where annual returns compound at high teens," Fundstrat's Tom Lee said.