The bushfire, which remains at an "advice" level alert, is contained but is burning east of Tennant Creek in an area of more than 9340sq km under "high to extreme" weather conditions.
Residents are being warned smoky conditions are expected to continue for days, as winds of up to 60km/h carry smoke far from the flames.
Authorities said the Barkly Highway fire was tracking to be one of the Territory's largest and most significant in recent history.
The Barkly Highway is closed to traffic between Threeways Roadhouse and Barkly Homestead and motorists are urged to delay travel in the area until conditions are clear.
Three fire bombers are positioned in Tennant Creek, and two strike teams with tankers have been deployed from South Australia, NT Police, Fire and Emergency Services said on Sunday.
NT Police Commissioner Michael Murphy said all measures were being put in place to protect people and assets from the fire, which had an edge extending hundreds of kilometres.
"Our thoughts and thanks are with the pastoralists who are working incredibly long hours protecting their property and stock, and we thank all the hard-working frontline personnel leading, surveying and putting in mitigation strategies to minimise the impact of this large and uncontrolled fire," he said in a statement.
A fire ban will remain in place for Darwin and the Adelaide River, Gregory South-East and Barkly North areas until Tuesday.
A health alert has been issued for Tennant Creek and the surrounding areas impacted by smoke, while residents in the Barkly region are urged to make fire preparations.
The Bureau of Meteorology has advised wind conditions across the Barkly will ease on Wednesday, but high extreme fire weather has been forecast for the rest of the week.
19°C