But such forecasting has been made difficult by the "fiscal cliff" — the confluence of spending cuts and higher taxes that kick in automatically next year if politicians in Washington can't reach a deal.
But others say if it isn't the fiscal cliff, it would be the debt ceiling or some other Washington-manufactured crisis to worry investors. They recommend that investors look past the immediate policy crisis and think long term. After all, they say, most investors are saving for college or retirement — goals that are many years off.
"There is life after the fiscal cliff," said Craig Fehr, an investment strategist with Edward Jones in St. Louis.
Even with all the uncertainty now, some experts feel comfortable making a few predictions for the new year. The economy, they say, will continue to grow at a modest annual rate of 2 percent to 2.5 percent. Interest rates will remain low, a challenge for savers and bond investors.
The U.S. stock market will post a gain, but not as much as this year. The S&P 500 index, a broad measure of market performance, is up nearly 12 percent this year. The market will go up by 6 percent to 10 percent, forecasters say.
And no matter what kind of resolution Congress and the White House reach on the fiscal cliff, higher taxes and lower government spending next year are a safe bet.
"The debate in Washington now is what magnitude and who gets hit," said Wayne Lin, portfolio manager with Legg Mason Global Asset Allocation in New York.
Here are other observations for the 2013 outlook:
Several signs bode well for the stock market here.
"A lot of corporations are loaded with cash. They have not spent it. They have not hired new workers," said Jerry Scheinker, an executive vice president with Janney Montgomery Scott's Baltimore office. "The economic numbers are better. The housing numbers are better. Clients are finally more positive about investments, instead of keeping money in CDs and Treasury bills and bank accounts."
Chicago-based Morningstar tracks 1,500 stocks, mostly in North America. Under a formula that takes into account future cash flow and current stock prices, Morningstar concludes that the median stock going into 2013 is mildly undervalued. In other words, at least half the stocks are selling for less than they're worth.
Lin also leans toward U.S. stocks, rather than international equities. He noted that currency volatility puts investors at exchange-rate risk.
Some investment professionals recommend stock in companies that regularly increase their dividends, even though the tax rate on this income is set to go up next year.
"Over time, those are the best performers," Fehr said. "We don't think that track record changes because tax rates change."
Scheinker added that even if investors must pay more taxes on dividends, that's still better than earning meager interest on a certificate of deposit and paying taxes on that.