The US state of California has proclaimed a state of emergency to prepare for what is shaping up to be a potentially historic El Nino season.The proclamation will mobilise state resources and accelerate preparations ahead of potential winter storms, coastal flooding and other impacts, according to a statement from the governor's office on Monday (local time).

"The emerging El Nino event is already breaking records, and forecasters expect it to continue to strengthen, potentially becoming the strongest in recorded history," the statement said.