US-based Enough Project says Upper Nile, Jonglei and Unity states are likely to experience intense floods by the beginning of next year.
It says the condition is caused by El Nino, a temporary effect of climatic change in the region around the Equator.
The Enough project says scarcity of rains from July to September this year, which was later followed by unsteady rains, should result into floods by the by the start of 2016.
In a statement, the Enough Project says the El Nino condition is likely to affected people living in the Greater Upper Nile because they do not have sources of income, and facing rising prices of food prices.
“Externally, the effects of El Niño, which in the beginning of the planting season seemed promising, have taken a turn for the worse,” partly read the statement.
“Rainfall deficits occurred in July through September, and higher-then-average rainfall, which could result in floods, is predicted for the start of 2016.”
It also warns that Upper Nile Jonglei, and Unity states, which are the most affected by the conflict, will also become difficult to access.
The Enough Project also noted food insufficiency has become persistent in Protection of Civilians Sites across the country.