The UN's Resident Coordinator, Osnat Lubrani, says communities and governments need to prepare now for the extreme weather changes El Niño usually triggers.
He says some countries are already implementing or drafting drought plans and the UN is ready to help co-ordinate this and to provide technical advice.
Over the coming months, countries on the equator can expect more rain, flooding and higher sea levels, presenting challenges for low-lying atolls already feeling the impacts of climate change.