Up to 30 firefighters could be at the Tangoio forest fires site each day for more than a month before it can be confirmed that the fire is finally extinguished.
Confirming the prolonged wash-up, principal rural fire officer Trevor Mitchell also warned that while managing the 350 hectare fire-ground is one thing, the wider Hawke's Bay faces looming greater fire risks with no "appreciable" rain forecast in the next fortnight ahead of the hottest and driest days of the summer.
"It's only going to get worse," he said today.
"But we can't change the weather. We all need to be very vigilant."
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There had already been indications of things to come, with the Tangoio fire contained within a 12km perimeter being just one of about 10 summer fires stirred up by the wind in Hawke's Bay in just four days, starting with a similarly-large resources deployment at the Waipukurau refuse transfer station last Friday.
At least eight fires were reported in a few hours on Monday, as far apart as Mangaorapa in Southern Hawke's Bay and Mohaka in the north.
The former was thought to have been the rekindling of a tree and scrub burn-off presumed to have been extinguished several months ago.
Authorities are now calling on people to take particular care to avoid a repeat or worse as breezes dry out the region heading into the seasonal high-risk period of late January and early February.
"Anything that is spark-hazardous needs to be treated very carefully," Mitchell said.
"What we need to flag right now is that people do need to be very careful. If slashing and mowing do it early in the morning."
The potential is highlighted by figures from last summer.
Niwa meteorologist Ben Noll said Napier's Nelson Park weather station had six days with temperatures over 30C between January 15 and the end of February, and many others over 25C.
The high, he said, was 34.8C on January 28.
It was 32.2C in Hastings, and 30.5C in Wairoa, but Hawke's Bay Today reported several private property and unofficial readings of around 40C in some areas.
Speaking today after Niwa's annual climate summary release, Noll said the area from Napier south is already "abnormally-dry" and "small pockets" of Central Hawke's Bay are rated "very dry".
Among features of the summary was that Dannevirke last year had its lowest annual rainfall in at least 68 years, and of the prospects for the region Noll said: "With the lack of rain in the forecast, not only for Hawke's Bay but also the rest of New Zealand and which will be watched by farmers and the horticulture industry, it's not the best of news."
Mitchell said that at Tangoio there remained an "awful lot" of underground hotspots, and completing the job would take time.
"It's a matter of securing the perimeter then working our way into the middle," he said. "Unfortunately there's no quick fix."
Fire management have been working on a plan including rostering 25-30 people a day for four to five weeks, including ground firefighters, machine operators, and those overcoming the problem of a lack of water source "on the hill."
Meanwhile, among features of the Niwa summary was that much of Hawke's Bay had temperature maximum last year were more than 1.2 per cent above average and parts had just 50-79 per cent of average annual rainfall.
A feature temperature high was the 34.1C maximum in Wairoa on November 27, the town's highest November reading in 55 years of comparable detail.