Watch Cashin: This could spark 'outright selling'

Art Cashin says CNBC viewers and users need to keep watching the yield on the 10-year U.S. note.

Speaking after the Federal Reserve released the minutes from its December policy-making meeting at 2p ET, Cashin, UBS' director of floor operations at the NYSE, told CNBC's Bob Pisani if "we get up around 3.15 (percent) they'll start to put a little further pressure on stocks. And 3.25 can bring outright selling, I think."

Cashin said the Fed minutes indicate the central bank's staff is getting more optimistic about the economy's future, which could mean a quicker tapering, but "with no disrespect intended, however, the Fed staff is historically very poor at forecasting."