The trio and their dog failed to return from a day trip into the local bush last week.

Alice Springs locals Claire Hockridge, 46, Tamra McBeath-Riley, 52, and Phu Tran, 40, were last seen in Alice Springs on Tuesday, November 19.

NT police have failed to find them even after an exhaustive search by air and land after they were reported missing on Saturday, four days after they were last seen.

Temperatures over the past week have reached extreme levels or more than 40 degrees on some days.

The group are believed to be travelling in a late model white Mitsubishi Triton, possibly with SA registration and had a dog on board.

Police have made a number of inquiries in relation to the whereabouts of the group and launched an air search of the Stuarts Well and Owen Springs area yesterday.

Police hold concerns for the group as it is unusual for them not to be in contact with family members, and encourage anyone who may have information which may assist with investigations to contact them.

Anyone with information as to the whereabouts of Claire, Tamra and Phu are urged to contact police immediately on 131 444 or report it anonymously via Crime Stoppers on 1800 333 000 reference PROMIS number 9140905.

The three had told friends and family they were going for a drive south of Alice Springs, but failed to return that night.

Superintendent Pauline Vicary said police are now calling for public assistance from anyone who had any contact with them in the days leading up to their disappearance, or has seen their vehicle to call police.

"At the time they left, it is believed Claire was wearing blue jeans, a dark blue short sleeved t-shirt and a red patterned bandanna, and Phu was wearing tan coloured cargo shorts with a red t-shirt. We don't have any information as to what Tamra was last seen wearing."

The group were travelling in a white Mitsubishi dual cab Triton ute with South Australian registration S483 AAI.

The vehicle has a black soft tonneau cover, a front nudge bar with two round lights, a UHF aerial and a black bonnet strip.

A pet grey/blue coloured Staffordshire bull terrier is with the group, and it is not known what supplies of food or water, if any, they had taken with them.

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