NOAA’s Climate Prediction Center: La Niña is back
September 8, 2011
La Niña, which contributed to extreme weather around the globe during the first half of 2011, has re-emerged in the tropical Pacific Ocean and is forecast to gradually strengthen and continue into winter. Today, forecasters with NOAA’s Climate Prediction Center upgraded last month’s La Niña Watch to a La Niña Advisory.
NOAA will issue its official winter outlook in mid-October, but La Niña winters often see drier than normal conditions across the southern tier of the United States and wetter than normal conditions in the Pacific Northwest and Ohio Valley.
“This means drought is likely to continue in the drought-stricken states of Texas, Oklahoma and New Mexico,” said Mike Halpert, deputy director of the Climate Prediction Center. “La Niña also often brings colder winters to the Pacific Northwest and the northern Plains, and warmer temperatures to the southern states.”
Climate forecasts from NOAA’s National Weather Service give American communities advance notice of what to expect in the coming months so they can prepare for potential impacts. This service is helping the country to become a Weather Ready Nation at a time when extreme weather is on the rise.
hurricane forecasters factored the potential return of La Niña into NOAA’s
updated 2011 Atlantic hurricane season outlook, issued in August, which
called for an active hurricane season. With the development of tropical
storm Nate this week, the number of tropical cyclones entered the
predicted range of 14-19 named storms.
La Niña is a naturally occurring climate phenomenon located over the tropical Pacific Ocean and results from interactions between the ocean surface and the atmosphere. During La Niña, cooler-than-average Pacific Ocean temperatures influence global weather patterns. La Niña typically occurs every three-to-five years, and back-to-back episodes occur about 50 percent of the time. Current conditions reflect a re-development of the June 2010-May 2011 La Niña episode.
NOAA's National Weather Service is the primary source of weather data, forecasts and warnings for the United States and its territories. NOAA’s National Weather Service operates the most advanced weather and flood warning and forecast system in the world, helping to protect lives and property and enhance the national economy.