The latest international measurements show El Nino looks set to remain strong throughout summer and into Autumn.

Water temperatures appear to be 2 degrees warmer than usual along the equator.

NIWA forecaster Chris Brandolino said usually anywhere from a half-a-degree to point-seven-degrees Celsius warmer would meet the threshold for an El Nino.

Mr Brandolino said the fact current measurements are three- to four-times more than the threshold is unusual, even for an El Nino.