Don't overreact to every breath of a downturn; with diversified investments, you have shelter from the storm, say financial experts.

WASHINGTON — The stock market is plummeting, the housing market is tanking, and talk of recession has reached a fevered pitch. So what does this mean for the American consumer?

If you've got a mortgage, is it a good time to refinance now that the Federal Reserve has slashed the federal funds rate? If you've got credit card debt, will your rates decrease? And what about the stock market? Buy, sell or sit tight?

The good news is, you should see lower interest rates on student loans, credit cards, home-equity lines of credit and some mortgages. But keep in mind that the subprime mortgage meltdown has produced a tighter credit market. That means you will need solid credit and, in the case of refinancing, enough equity in your home to reap the benefits.

Investment strategies depend on your stage in life, but financial advisers said they are giving their clients, regardless of age, one simple piece of advice: Stay calm. If you've got a diversified, not-too-aggressive financial plan, you should be able to ride out the turbulence.

"The worst thing anyone can do is react to these market events," said Fran Kinniry, a principal at Vanguard Group.

Ambler Cusick, a financial adviser at Smith Barney, put it bluntly: "Don't do anything stupid."