WASHINGTON — La Niña, the cool flip side to El Niño, is returning for a second straight winter, forecasters said Thursday.

The National Oceanic and Atmospheric Administration said a weak La Niña has formed and is expected to stick around for several months. La Niña is a natural cooling of parts of the Pacific that alters weather patterns around the globe.

La Niña typically brings drier conditions to the U.S. South and wetter weather to the Pacific Northwest and western Canada. Indonesia, the Philippines, northeastern South America and South Africa often see more rain during La Niña winters.

Last year's La Niña was unusually brief, forming in November and gone by February. This one should hang around through the end of winter. While it may last a bit longer than last year's La Niña, it should be just as weak, said Mike Halpert, deputy director of NOAA's Climate Prediction Center.

Texas A&M University agricultural economist Bruce McCarl said La Niña years are often bad for Texas and the surrounding region.

U.S. production of most crops — except corn — generally goes down in La Niña years, according to research by McCarl.

The last major La Niña several years ago caused major crop damage and Texas suffered a devastating drought, McCall said.

On average, La Niña years hurt U.S. and China gross domestic product about 0.3 percentage points, but lead to growth in India, New Zealand and South Africa, according to Kamiar Mohaddes, a University of Cambridge economist.

Because La Niña shifts storm tracks, it often brings more snow in the Ohio and Tennessee Valleys.

"Typically La Niña is not a big snow year in the mid-Atlantic," Halpert said. "You have a better chance up in New England."