Traditionally, the holiday season is extremely dry and a small spark can cause a major fire.
But Niwa scientists say substantial rainfall across the South Island recently has contributed to moderate-to-large increases in soil moisture levels in the vast majority of the island.
A Niwa spokesman said the most significant increases occurred in Tasman, Nelson, Marlborough, Canterbury and North Otago.
"The driest soils across the South Island compared to normal for this time of the year are found in coastal Hurunui district, while the wettest soils for this time of the year are found in northern Fiordland and the Queenstown-Lakes district.
"Due to the rainfall in the past week, most hot spots have dissipated. However, a hot spot still remains in coastal Hurunui district."
Because of expected rainfall, it was likely soil moisture levels would continue to increase in the west in the coming week, while smaller increases were expected in Southland, Otago, Tasman and parts of Marlborough.
However, Fenz Otago district principal rural fire officer Graeme Still urged holidaymakers, especially those in Central Otago, not to be complacent.
Because of the wet weather, it was an open fire season everywhere in the region, except for Central Otago where it was still restricted.
"Alexandra, Clyde and Cromwell are the driest parts of the region. Yes, there has been some rain there, but it’s not enough to lift it out of restricted.
"It only takes a spark to cause a devastating wildfire like the one at Deep Stream recently.
"There was a lot of moisture in the ground, but we still had a 5000-hectare fire.
"Some grasses dry really fast with a bit of wind."
He suggested people visit the Fenz website — www.checkitsalright.nz — before lighting a fire, to make sure it was safe in their area.
Some fires required a permit, he said.
