The Bendigo helicopters have been dispatched to an out-of-control grass fire in Blampied, near Daylesford.
Police have blocked the Midland Highway to Ballarat and are diverting traffic away from the area.
The fire was reported about 2pm and 14 trucks are on scene with another 3 on route.
The Hepburn Advocate followed fire trucks to the scene but was evacuated when the blaze began to travel downhill towards fire crews.
The CFA has issued a watch and act notice for the areas of Bullarto, Bullarto South, Daylesford, Hepburn, Musk, Woodburn, and says it is expected to impact the areas between 4.45pm and 6.45pm.
Residents are urged to monitor conditions.
If you are experiencing any symptoms that may be due to smoke exposure, the Department of Health advises people to seek medical advice or call Nurse on Call on 1300 606 024.