Police are conducting a land and air search in Kakadu National Park for a woman who is believed to have been there since Thursday but has not contacted her family in that time.

Acting Senior Sergeant Steve Langdon said in a statement police believed 35-year-old Jessica Louise Stephens had been missing around Nourlangie Rock, where they thought she had been camping since Thursday.

He said Ms Stephens has not contacted her family in a week, and while her vehicle had been found, Ms Stephens had not.

The search for her began on Tuesday morning, involving 22 Kakadu rangers and ten police officers using two and four wheel motorbikes, and two helicopters.

“This operation remains a search and rescue with items collected yesterday suggesting that Jessica was mobile as early as yesterday morning,” Snr Sgt Langdon said.

“Temperatures in the area are forecasted to reach 41 degrees, and the terrain in Kakadu is unforgiving. However, we have multiple assets deployed into the area and we remain hopeful that we will find Jessica safe and well,” he said.

Police are urging anyone who has sighted Ms Stephens, or has information about where she is, to call 131 444.