At first glance, Wednesday's 35-point pullback by the Dow Jones Industrials (^DJI -0.51%)  looked like a natural pause after the average soared almost 1.5% on Tuesday. But with the vast majority of stocks already having reported their earnings for the final quarter of 2013, investors are looking to what will come next month from first-quarter 2014 results. As the Federal Reserve confirmed in its Beige Book report today, the bad winter could well have a negative impact on the U.S. economy this quarter, especially among the retail and consumer goods areas and especially in the East Coast areas hardest hit by the weather. That in turn explains some of the skittishness among Dow components Nike (NKE -0.88%), Wal-Mart (WMT -0.10%), and Visa (V -0.02%) today.

Nike's 1.5% drop came in the wake of bad news from rival Adidas, which said overnight that poor performance in emerging-market currencies compared to the euro would have a big impact on its earnings and revenue this year. The U.S. dollar has been similarly strong compared to most of those currencies, potentially giving Nike the same exposure in its own financial results. Yet even though Nike's international business plays a huge role in its overall revenue, any sluggishness in U.S. results would also make investors worry about the athletic-apparel giant's future. With Nike set to kick off earnings season later this month because of its unusual fiscal year, investors should get an early sense of how the cold winter has affected its sales.

(WMT -0.10%)

(V -0.02%)

The good news for long-term investors, though, is that weather-related phenomena are by their nature temporary. If share prices fall as a result of momentary setbacks, that only sets the stage for rebounds when things return to normal -- and smart investors will grab opportunities on stocks they're interested in for the long haul.