The U.N. weather agency says the likelihood has increased of La Nina conditions occurring during the remaining months of 2011, potentially prolonging the drought in the Horn of Africa. The La Nina phenomenon is associated with cooler sea surface temperatures in the central and eastern tropical Pacific, greater rainfall in the southern Pacific, and dry conditions in parts of east Africa, southwest Asia and the southern United States. The World Meteorological Organization says its latest forecasts are for a 50 percent probability of La Nina conditions, up from about 25 percent previously. WMO climate expert Rupa Kumar Kolli said Thursday that there is an equal chance of neutral conditions and almost no likelihood of an El Nino, according to a report of the Associated Press.
