A decrease in precipitation over the tropical region but regional changes, such as increases in rainfall amounts in western NSA of up to 40 mm, are expected by mid-century under RCP8.5 . Changes in the dry season in the central part of South America  due to the late onset and late retreat of monsoon, decreases in precipitation over the Amazon and central Brazil are expected . Further, an increase in the frequency and geographic extent of meteorological drought in the eastern Amazon and the opposite in the west are expected with medium confidence . A decrease in the total annual precipitation but an increase in heavy precipitation  are projected for a 2°C GWL  .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report