It can increase flooding in the Horn of Africa while making Southern Africa drier.
The events are likely to lead to a decrease in storm events in the Atlantic and the Gulf of Mexico and an increase in storminess in the eastern Pacific.
This El Nino has also impacted the South Asian monsoon.
"We are seeing that the Indian monsoon right now is almost 12% below normal. There is only a month left of the summer monsoon season making it difficult to recover," said WMO's El Nino expert Rupa Kumar Kolli.
"That was the kind of early warning information we can extract from the El Nino signal and it helps policy makers to prepare," he said.
Currently, the Pacific is seeing a surge of hurricane activity, with three category four strength tropical storms swirling around the Hawaiian islands.
Researchers say that these hurricanes can disrupt the predominant easterly trade winds that are found along the equator. This disruption allows more heat to build up in the eastern part of the Pacific, adding more fuel to stormy conditions.
But researchers cautioned that the scale of impacts, especially in the northern hemisphere, is very hard to read because there is also an Arctic warming effect seen in the Atlantic jet stream.
"The truth is we don't know what will happen. Will the two patterns reinforce each other? Will they cancel each other? Are they going to act in sequence? Are they going to be regional? We really don't know," David Carlson, the director of the World Climate Research Programme, told news agencies.