South America: Exceptional water deficits forecast for northern Brazil, surpluses in Paraguay, Uruguay, Argentina

Exceptional deficits may continue across much of northern Brazil and coastal Peru and Chile for the remainder of the forecast period. The extent, severity, and persistence of surpluses and deficits through May 2016 is evident in the 12-month map (below). The map is based on observed data through August and forecasts issued the last week of August 2015.

Colombia is suffering the worst drought and forest forest fires in the country's history. Water restrictions which include daily or weekly rationing have been imposed in some areas, as well as incentives and fines for water use.

Even as downpours stopped traffic and put out lights, Brazil's southern states of Sao Paulo, Rio Grande do Sul, and Parana welcomed recent rains, hoping reservoirs might recover some of their drought-depleted water - Sao Paulo's Cantareira Reservoir has fallen 80 percent in three years. Flooding further south on the continent displaced 4,000 people in Uruguay and 11,000 in Argentina.

As seen in the 3-month maps (below) surpluses are forecast in September for central Paraguay, southern Brazil, Uruguay, and Argentina, and are expected to increase in extent and severity through May 2016 with widespread exceptional surpluses anticipated.

Also evident in the 3-month maps is the forecast of a shift from deficit to surplus in northern South America March through May. Surpluses may begin to emerge in northern Peru, coastal Ecuador, and coastal Colombia December through February; and may continue to emerge in Colombia, Venezuela, and Guyana March through May. (It should be noted that forecast skill declines with longer lead times.)