David Stockman has long warned that the stock market is on the verge of a massive collapse, and the recent price action has him even more convinced than ever that the bottom is about to fall out.

"I think it's pretty obvious that the top is in," the Reagan administration's OMB director said Thursday on CNBC's "Futures Now." The S&P 500 has traded in a historically narrow range for the better part of 2015, having moved just 1 percent higher year to date. "It's just waiting for the knee-jerk bulls, robo traders and dip buyers to finally capitulate."

Stockman, whose past claims have yet to come to fruition, still believes that the excessive monetary policy from central banks around the world has created a "debt supernova," and all the signs point to "the end of the central bank enabled bubble," which could cause a worldwide recession.