February 2, 2006

La Nina to Affect U.S. Weather into Summer

By Christopher Doering

WASHINGTON -- The return of a La Nina weather pattern this year will likely mean drought in southern and southwestern U.S. states, government forecasters said on Thursday, adding it was too early to tell if La Nina would also lead to more Atlantic hurricanes in 2006.

La Nina is an unusual cooling of Pacific Ocean surface temperatures, which can trigger widespread changes in weather around the world. Forecasters with the National Oceanic and Atmospheric Administration said La Nina could wreak havoc on U.S. weather through late spring, and possibly into the summer.

"It's a minimal La Nina right now. It's just crossed the threshold," said Ed O'Lenic, meteorologist with NOAA's Climate Prediction Center. "There is some enhanced uncertainty as we get into the spring," he said.

La Nina is forecast to bring dry weather to parts of the South and Southwest from Arizona to Arkansas and Louisiana, NOAA said. The unusual weather pattern also will bring above normal precipitation to the Northwest and the Tennessee Valley area.

A lingering drought could be detrimental to the South, especially in Texas, the top cotton growing state in the country and whose farms are reeling from severe drought.

"(La Nina) is adding fuel to the fire," said Sharon Johnson, a cotton expert for First Capitol Group in Atlanta, Georgia. "We were already nervous about the potential to make a smaller crop this year because of West Texas" which is feeling the largest impact from the drought, she added.

NOAA also said that while La Nina can mean increased hurricane activity in the Atlantic Ocean, it was too soon to say what impact it will have this year.

Last year was the busiest Atlantic hurricane season on record, with 26 named storms and 13 hurricanes. Four major hurricanes made landfall in the United States, including Rita and Katrina, which pounded the U.S. Gulf Coast in August and September with heavy rains and wind.

NOAA previously warned that the hurricane season -- which typically peaks between August 1 and late October -- could be active again in 2006.

A La Nina weather pattern occurs about every three to five years. The last one was in 2000-2001, but it was relatively weak.

La Nina, which means "infant girl" in Spanish, is generally the opposite of an El Nino weather pattern where the ocean waters warm.

NOAA will release its U.S. spring weather outlook in mid-March and its forecast for the Atlantic and Pacific hurricane seasons in mid-May.

* NOAA La Nina site at http://www.elnino.noaa.gov/lanina.html