Growing fears for missing man amid sub-zero temperatures forecast for Alice Springs

The search for a man who failed to show up to work just hours after speaking with his family in the Northern Territory has entered day three, as sub-zero temperatures leave authorities growing more concerned.

Gach, 26, was last seen leaving his home in Alice Springs about 3.30pm on Monday.

He last spoke to his family on the phone about two hours before failing to show up to work later that night.

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His car, a red Mazda CX5 with NT registration CF05BH, was found by police the next morning on Larapinta Drive, almost 15km west of John Flynn's Grave Historical Reserve.

An intensive land and air search operation reached its third day today about 21km west of Alice Springs, with more than 50 emergency services and rangers scouring the area for Gach.

"Search efforts have been extensive, with significant contributions from local resources," NT Police Search Coordinator Acting Sergeant Chris Grotherr said.

"However, forecasted sub-zero overnight temperatures over the coming days are increasing our concerns for Gach's welfare."

Today, temperatures fell to minus 0.5 degrees.

They are expected to hit a low of two degrees tomorrow and zero degrees on Saturday.

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Search crews have already covered more than 500km of "challenging" terrain.

Gach is described as a six-foot-tall man of Sudanese appearance with a lean build and short curly hair.

He was last seen wearing a red or orange puffer jacket, cream-coloured tracksuit pants, and dark-coloured runners.

Anyone who may have seen Gach near Larapinta Drive, Standley Chasm or Simpsons Gap on Monday evening, or has knowledge about his whereabouts, is urged to contact police.

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