A new La Niña is developing, according to scientists with the Climate Prediction Center of the U.S. National Oceanic and Atmospheric Administration (NOAA). La Niña, which refers to a cooling of ocean surface temperatures in the central and east-central equatorial Pacific that occurs every 3 to 5 years, is expected to bring wetter than normal conditions in the Pacific Northwest and drier than normal conditions in the southwestern U.S. this fall.
“While we can't officially call it a La Niña yet, we expect that this pattern will continue to develop during the next 3 months,” Mike Halpert, acting deputy director of the Climate Prediction Center in Camp Springs, Md., indicated on 6 September. NOAA declares the onset of a La Niña when the 3-month average sea surface temperature departure exceeds −0.5 degrees C in the east-central equatorial Pacific. For more information, visit the Web site: http://www .cpc.ncep.noaa.gov/products/precip/ CWlink/MJO/enso.shtml.