Fire officials are urging caution, with temperatures set to soar in coming days.
Meteorological drought has now emerged in parts of Northland, Auckland, Great Barrier Island, and northern Waikato.
— NIWA Weather (@NiwaWeather) January 20, 2020
This is expected to expand over the next week.
More: https://t.co/RPJ4toPtIt pic.twitter.com/0ugLJYjWjU
Fire and Emergency is also prohibiting road-side mowing, grinding, welding, chainsaws and the use of fireworks and explosives in Otago in addition to the fire ban there amid "extreme" fire danger.
MetService is forecasting a hot and dry spell this weekend with fire danger spiking. Fire and Emergency is keeping a close watch on the top of the North Island and the east coast of the country as fire danger rises.
MetService is expecting temperatures to top 30C in many areas in coming days and with dry ground conditions already in much of the country, Fire and Emergency said those outdoors needed to be cautious.
Fire and Emergency rural fire manager Tim Mitchell said people should check fire restrictions, monitor fire danger and be vigilant with simple tasks, such as mowing lawns.
"Particularly in Northland it's been an incredibly dry season up there. They're in what we define as a meteorological drought situation ... so as a result of that the fuels - the grasses - are very dry and it wouldn't take much to ignite them," he said.
"The message to the public is it's going to be very warm and dry, particularly over the next few days. While we would always encourage them to take caution at this time of year around making sure they don't cause a wild fire, but over these next few days in particular it will be really important that they do take extra care, particularly in the outdoors with machinery and equipment, things like mowers that historically do start these fires."
MetService meteorologist Lewis Ferris said the warmest temperatures were expected on the South Island's east coast.
"The likes of Gore and Invercargill actually on Friday are looking as though they are going to see quite a departure from average. Invercargill is going for a high of 30 degrees on Friday. That's 11 degrees warmer than the average for this time of year."
Blenheim was expected to be the hottest spot with 33C forecast on Saturday.
Fire restrictions would come into place in Southland at 8am on Saturday following a prolonged period of dry and hot weather following Christmas.
The restricted fire season meant most fires now required a permit.
Most of Otago was also in a restricted season with fires prohibited in the region's Central zone, which included the Central Otago district, inland Waitaki district and Wānaka.
That ban was extended to mowing, grinding, welding, chainsaws, fireworks and explosives today.
Deputy rural fire officer Bobby Lamont says high temperatures and low humidity has made it easy for fires to ignite and harder to control.
Watering restrictions were also imposed in Stratford in Taranaki today but were lifted in Luggate in Otago.