Bay dairy farmers struggling with low payouts fear they could be hit with a "double whammy" with one of the worst El Nino drought-risk summers since 1997/98 predicted.
In its latest outlook report the National Institute of Water and Atmosphere (Niwa) revealed it is now 99 per cent certain that El Nino conditions would continue for at least the next three months.
Niwa scientist Chris Brandolino said the current event was tracking close to the 1997/1998 El Nino - the strongest since 1950 - and expected to further intensify between January to March.
From now to December above-normal pressure was forecast to the north and west of New Zealand, while below-normal pressure was expected to the east and south of the country.
Based on the three biggest El Nino events since 1950 the elevated risk of drought was expected later this summer, in particular for eastern parts of both islands and northern areas of the North Island, he said.