High winds in the Nelson Lakes area today are expected to frustrate searchers looking for a missing British tramper.
Andrew Ian Wyatt, 41, was last seen at Blue Lake in Nelson Lakes National Park on or about December 14.
Strong alpine winds were expected to continue until Friday, when the Air Force was due to join the search, police said.
"We've still got high winds in the alpine environment, so we can't get in there," Senior Constable David Cogger said. Search teams were waiting on standby in case conditions changed.
Mr Cogger said police were still speaking to people who had been tramping in the area, but there had been no new sightings reported.
Police were going to attempt to trace Mr Wyatt's banking records, but public holidays had delayed getting his banking details from the United Kingdom.
"And his banking literature is on his laptop, which is locked and is flat.
"We're still trying hard, you've got to keep going and going and going."
In the area Mr Wyatt was tramping, he had two options of paths to travel, either towards the D'Urville Valley or the Waiau Valley, Mr Cogger said.
Mr Wyatt also failed to fill in log books at Department of Conservation huts, "so we've got no real starting point".
He had a back country pass, which meant he could have stayed in any of the huts for free, so there was no reason not to fill in the books, Mr Cogger said.
Police knew Mr Wyatt's planned route, but his plan was decided in November and weather could have changed his plans since that time, he said.
He was intending to tramp to the Boyle Village in Lewis Pass, where he was due to pick up a food package on December 16, but he never arrived.
His intention was to then carry onto Arthurs Pass where he had another food parcel to collect, police said.
Police have been in contact with his parents in Cornwall, England, who said they had not heard from him since December 12.
Mr Cogger said Andrew Wyatt had been in email contact with his father. "I think any parent would be concerned about the well being of their children when they're 12000 miles away," he said.
Police still want to speak to anyone who was tramping in the Blue Lake, Sabine Valley, D'Urville Valley area of Nelson Lakes National Park between December 13 and 19.
Contact Nelson Police on 03 546 3840 urgently. The Police event number is P015791441.
Mr Wyatt is 180cm tall, with ginger hair and was carrying light equipment.
