The climatic conditions observed in Brazil during October 1998 were typical of a transition season from winter to summer. Isolated thunderstorms dominated the convective activity over the Amazon. The frontal systems moved fast over the Southern Region and were slow and active over the West-central and Southeastern Regions. Cold air masses penetrated into Southern Region, Mato Grosso do Sul and the coastal belt of the Southeastern Region, causing fall of temperature and little rainfall. The highest monthly rainfall totals occurred in the northwestern Amazonas, Vale do Paraíba (São Paulo State) and the western belt of Southern Region. In the upper troposphere the Bolivian High and the Northeast through have formed to the west of their normal climatological position.

The area of negative SST anomalies in the Equatorial Pacific increased in relation to that observed in September. All the global climatic conditions monitored this month indicate a favorable situation for the configuration an maintenance of the La Niña phenomenon.

[Índice]