The search for missing trampers Jessica O'Connor and Dion Reynolds has been abandoned because of heavy rain.
But searchers have found some hopeful leads, police said.
"Search teams have located further historic footprints and camp sites in the search area, but it is not known yet if they belong tothe missing trampers," a police spokeswoman said.
Active searching was not likely to take place tomorrow as the weather is expected to worsen with heavy rain "preventing safe activity in the field", she said.
A severe weather warning has been issued for Nelson west of Motueka with heavy rain expected overnight.
The hunt for the pair began on May 19 with police, volunteers, the New Zealand Defence Force, Urban Search and Rescue, Land Search and Rescue and the fire service pitching in. A team from Alpine Cliff Rescue Mt Cook yesterday joined the search effort.
Searching resumed this morning with weather conditions being monitored.
Settled weather has been a blessing so far, but police warned yesterday the incoming bad weather would hamper their efforts.
In a statement this afternoon police said up to 100ml of rain was expected in the area in the next 24 hours.
"As such, search efforts will focus on areas that are safe to operate in through the rain, and teams in more exposed areas will pull out for their safety."
An earlier aerial shoreline search from the Kahurangi Lighthouse north to Farewell Spit had not found anything of note, the statement said.
🌧 is on the way for Sunday as a complex low pressure system approaches from the Tasman Sea. Severe Weather Watches and Warnings for periods of heavy rain. Details at https://t.co/qHyE5zhh6X ^Tahlia pic.twitter.com/PzOeZyLXO7
Rain was forecast to develop from midday in the national park, becoming heavy at times from the afternoon, according to MetService. Northerly winds are expected with gales in high places later before easing overnight.
A heavy rain warning is in place from 4pm, ending at 5am Monday.
Between 70-100mm of northerly rain is expected to accumulate over that time, with peak rates of 10-15mm an hour.
"Heavy rain may cause streams and rivers to rise rapidly. Surface flooding and slips are also possible and driving conditions may be hazardous," MetService warns.
