The El Nino has yet to make its presence felt on New Zealand dairy production, although the event still has some months to run.
Latest data from the Dairy Companies Association of NZ showed national milk production was down 2.1 per cent in November compared with the same month a year ago, and was down by 3.1 per cent in the season to date.
Analysts said it was difficult to gauge the exact impact on production that El Nino would have throughout the remainder of the dairy season, but that rain since the New year would have been useful for many farmers.
More rain is forecast throughout the country for the next week.
Fonterra's next production update is expected to show the co-operative is on track for 6 per cent drop in the 2015/16 season ending on May 31, based entirely on low milk prices.
NIWA principal forecasting scientist Chris Brandolino said much of the country enjoyed rain on New Year's day and in the days following, but that the El Nino weather pattern had some way to go.
"It was looking dire up until New Year's day but rain has helped the North Island and there has been some rain in mid and north Canterbury as well," he said.
"Yes, there has been some alleviation of the dryness in the northern and eastern parts of the North Island as well as part of Canterbury but over the summer season, going in to early Autumn, drier than normal conditions is the most likely outcome for the northern part of the North Island," Brandolino said. "We still think that there will be dryness in some parts of the country, but every El Nino is different," he said.
There was also the prospect of more rain in the second half of the tropical cyclone season, and El Nino could have an impact on their strength and frequency.
For the North Island, "hotspot" areas are present in extreme western Northland, central and southern Waikato, extreme eastern Gisborne, parts of the Wellington region, south coastal Taranaki as well as west coastal Manawatu-Whanganui regions, NIWA said.
Eastern areas of the island south of Gisborne were also experiencing dry conditions, NIWA said.
For the South Island, a hotspot exists between Ashburton and just north of Oamaru in eastern Canterbury, NIWA said in its latest weather assessment.
While farmers are facing challenging conditions and low dairy prices, the New Zealand dollar is providing some offset. The currency hit a low of US64.20c on Friday, down about US4c or 5.6 per cent since the end of 2015.