Latest data on soil moisture shows a number of regions are experiencing drier than usual conditions.
NIWA's weekly 'soil hotspot' update shows soil moisture levels across the North Island generally decreased during the past week, due to lower than average rainfall for this time of year.
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"While decreases were observed nearly everywhere, the most notable change over the past week occurred in western Auckland and lower Northland, where soil moisture levels went from near normal to drier than normal for this time of year," said the report.
"The Central Plateau to Manawatu-Whanganui also saw a significant decrease in soil moisture in the past week," it said.
The only area that saw slight soil moisture increases during the past week was East Cape.
The driest soils across the North Island compared to normal for this time of the year are found in an area stretching from coastal Manawatu-Whanganui northeast to Taupo.
The wettest soils for this time of the year are in coastal Wairarapa, East Cape, western Bay of Plenty and the Coromandel Peninsula.
The hotspot (which indicates low moisture levels) in Manawatu-Whanganui grew over the last week and is now covering parts of the Rangitikei and Manawatu Districts.
Across the South Island, soils remained much wetter than normal for the time of year from central Canterbury to Southland. In addition, soil moisture levels are also above normal in the Kaikoura District. Conversely, soil moisture levels continued to decrease this week across Nelson, Tasman, and the West Coast.
The driest soils across the South Island compared to normal for this time of the year are found in far southern Westland District, while the wettest soils are southern Canterbury and coastal Otago.
The report said a small hotspot has emerged in Nelson in the past week.