Cashin warns: This could be 'tripwire' for stocks

Art Cashin says investors should carefully watch the 10-year U.S. note yield. If it goes over 2.85 percent, stocks could suffer.

Cashin, UBS' director of floor operations at the NYSE, told CNBC's Bob Pisani around midday that "traders down here think that could be a tripwire. Above that, we'll see pressure on stocks."