Here Comes La Nina

The hurricane season still has a few weeks left. But there's another weather troublemaker waiting in the wings.

La Nina could be causing weather headaches throughout the winter, reports CBS News Correspondent Bill Whitaker.

There's been a massive change in the weather. NASA scientists reported Monday that the red-hot El Nino, which dominated world weather last season, is long gone, shoved aside and replaced by the cold ocean system called La Nina. Over the last couple months, cold water temperatures have stretched more than 5,000 miles over the tropical Pacific ocean.

While El Nino drenched California, La Nina typically dries the state out, sparking a wilder-than-usual fire season. Last year, El Nino blew Atlantic hurricanes away. Cool La Nina usually spawns more of them, like the current monster Mitch and its deadly predecessor, Georges. This winter across the country, expect the flip side of last.

NASA scientist Antonio Busalacchi reports that, since June 1998, the sea surface temperature has fallen 3 to 6 degrees, sea level has dropped 8 to 10 inches, and trade winds have increased across the Pacific - all La Nina conditions which are expected to persist for the next several months.

Past Ninas have brought drier and warmer weather across the southern tier of states and more precipitation over the northern-tier states. The engine of all this wild weather is the tropical Pacific, which sizzled up with El Nino and now, like a pendulum, is swinging way back, as much as 10 degrees below normal.

The good news: This is a relatively mild Nina.

The bad news: It's likely to linger through next spring.