Some investors believe a strong January means a strong year. If bulls use that to gauge 2013, they can prepare for disappointment, according to Byron Wien, vice chairman of Blackstone Advisory Partners.

The market has gotten ahead of itself and Wien believes there will be a sell off.

The Dow finished January up 5.8 percent, the highest rise since 1994, according to S&P Capital IQ data reported by The Associated Press. Not trailing far behind, the Standard & Poor’s 500 ended with gains of 5 percent. That index has not kicked off a better start since 1997.

Video: Economist Predicts 'Unthinkable' for 2013

“There's not a whole lot of bears left here,” Jeff Hirsch, editor of the Stock Trader's Almanac, told the AP.

Many pros point to history, which shows a rise of this magnitude tends to lead to double-digit gains for the year, CNBC noted.

And as the prospects have seemed to brighten, investors are coming off the sidelines. The $51 billion in net deposits that moved into stock funds and so-called hybrid funds in January was the highest levels seen since 2004, according to Strategic Insight data cited by the AP.

“The best time to buy stocks is when most people are negative on them,” Wien told CNBC. “Right now, sentiment is optimistic, if not euphoric. So I think the market is vulnerable right here. But it can get more vulnerable.”

Wien foresees this as a year profit margins peak, earnings decline and revenue growth slows.

“I expect the S&P to end the year about where it started,” he said. “The stock market had a good January, but I think we end where we started.”

Right now financial assets have streams of liquidity from the Fed. “But eventually the corporate fundamentals will take over. And I think they are going to be disappointing,” Wien told CNBC.

When the markets weaken, he foresees gold reaching $1,900 an ounce this year.

“I buy gold as an insurance policy. If the market is turbulent, you will be glad you own gold,” he said.

Marc Faber, managing editor and publisher of the Gloom, Boom & Doom Report, also holds gold as an insurance policy.

“I just think that government will print money and that there will be competitive devaluation, and so I want to have gold as an insurance policy,” he told CNBC.

In his January Market Commentary, Faber predicted that gold would fall to $1,550 to $1,600 an ounce, according to CNBC. Still, he wrote that he planned to increase his gold position on any further weakness, despite his concerns that strength of the U.S. dollar could be a headwind for a strong gold rally.

Video: Economist Predicts 'Unthinkable' for 2013