Sell in May and go away?
Spring is known as a season of rebirth and renewal. For golfers like me, it also means The Masters golf tournament, known as "A Tradition Unlike Any Other." Unfortunately for investors, another tradition unlike any other, the inescapable "sell in May and go away" effect, is playing out just as intended thus far. After beginning the month with a 65-point positive head-fake, the Dow Jones Industrial Average (INDEX: ^DJI) has done nothing but march lower. In golf terms, that's like starting your round with a birdie, only to follow it up with six-straight bogeys.

It's all in the data
In addition to continued focus on Europe, investors will be paying close attention to weekly jobless claims data out this morning. Expectations call for a rise of 5,000 to 370,000, with anything meaningfully above that likely to weigh on stocks in early trading. Also, expect natural-gas stocks like Chesapeake Energy (NYSE: CHK) to move on the U.S. Energy Information Administration's weekly natural-gas storage report, due out at 10:30 a.m. EDT.

Stocks in focus
Unfortunately, earnings from Dow component Cisco Systems (Nasdaq: CSCO) won't help matters this morning. Though it topped expectations for the quarter, the networking juggernaut disappointed onlookers with its forecast, indicating that the company's visibility into future customer spending is becoming increasingly cloudy, given the European recession and broad-based apprehension within its customer base.

Away from the Dow, eyes will be on earnings after the close from Nuance Communications (Nasdaq: NUAN). The speech recognition outfit, known as the engine driving Apple's (Nasdaq: AAPL) popular Siri application on the iPhone 4S, is expected to report earnings of $0.41 on roughly 25% revenue growth. While there shouldn't be any surprises, given that the company preannounced positive numbers only days ago, expect plenty of discussion on the earnings call regarding customer wins and future applications of its technology on tablets and televisions.

Making sense of the noise
Emotional decision making is an investor's worst enemy. While it's easy to get caught up in the day-to-day gyrations of the stock market, the best course of action is to develop a well-thought-out investment strategy based on your personal goals and circumstances -- and stay the course. It also doesn't hurt to have some great help. Our financial planning pros at The Motley Fool can do just that, which is why we're offering a special report entitled "3 Stocks That Will Help you Retire Rich." It's yours free for a limited time only.