Several market factors suggest that stocks are on track for a gradual yet significant move lower—potentially as much as 8 percent to 10 percent, Nick Colas, managing director at ConvergEx told CNBC's "Fast Money" on Tuesday.
Colas said he had three main reasons for being bearish on the market: continued interest rate volatility, ETF outflows and declining earnings estimates. "That puts a pin in the bubble notion that valuations continue to be cheap."
These conditions could result in an 8 percent to 10 percent move lower for stocks—a "grinding, kind of exhausting move to the downside over the course of a month or six weeks," he said. "We're not going to get any one-day event that really pushes us down. It's going to be a slow grind, which feels very painful when it's happening."
Despite calling the CBOE Volatility Index a "flawed indicator," Colas said that it's important for investors to keep in mind as a gauge of investor sentiment, and if the VIX moves over 20, "it's definitely time to take a look" and expect larger moves.
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When asked if he would short the market now, he was hesitant, because there is no single catalyst set to cause a sell-off.
"This is more about the market trending downward versus saying you've got to get out and get short here," he said. "Valuations aren't stupid, they are just, I think, full."
— By CNBC's Paul Toscano. Follow him on Twitter @ToscanoPaul