As the major search operation entered its fourth day on Saturday, police said officers - along with search and mountain rescue teams - will be working in Hamsterley Forest and the surrounding areas to look for any trace of her.
"We want to thank the public for their ongoing support and whilst we appreciate the offer of volunteers, we would ask that people do not join the search themselves as this could disturb the ongoing work and potentially distract expert sniffer dogs," police said in a statement.
Chief Inspector Dean Haythornthwaite said families out in the forest should "allow those officers the space to carry out their search and try not to disrupt that search area".
On Friday, officers said they were becoming "increasingly concerned" as the search concentrated on running trails between Eggleston and Hamsterley used regularly by Ms Hall.
Digital intelligence officers have also carried out extensive inquiries into Ms Hall's mobile phone, smart watch and running apps, but the force said "none have yielded any results unfortunately".
