Brazil's National Space Research And Climate Studies Centre said that in the first five days of January the Mantiqueira mountains near Rio de Janeiro received half the usual average monthly rainfall.
 
More rain was likely to fall this weekend, the centre said.
 
Mudslides killed 16 Brazilians in Petropolis, an historic mountain resort near Rio, in January 2003. In December 2001, 52 people died in mudslides in Rio de Janeiro state.