An advice message issued at 4.23pm on Thursday said the authority had contained the fire in Big Desert Wilderness Area and Big Desert State Forest that was burning out of control 41 kilometres north north west of Yanac.

The message was issued for Big Desert, Telopea Downs, Waggon Flat, Netherby, Yanac, Murrayville, Cowangie and Corina.

Forest Fire Management said firefighters would be patrolling the bushfire for at least the next three days.

Smoke may be visible from nearby roads and communities, including the Nhill-Murrayville Road where visibility was reduced. Smoke over road signs are in place.

Motorists are advised to use caution with emergency vehicles the Nhill-Murrayville Road.

The two fires in Big Desert Wilderness Area and Big Desert State Forest were a combined 1676 hectares in size.

Forest Fire Management Victoria said there was currently no threat to communities from fires in the region, but people should continue to stay informed and monitor conditions using http://emergency.vic.gov.au/.

Update, 2.40pm: The Country Fire Authority has declared a total fire ban for the Wimmera, South West, North East and East Gippsland districts on Friday.

The CFA said the fire danger rating for the Wimmera would be very high.

No fires could be lit or be allowed to remain alight in the open air from 12.01 AM on Friday until 11.59 PM.

The CFA advised people living in areas at risk of fire to activate their bush fire plan.

A bushfire in the Big Desert Wilderness Park and Big Desert State Forest was out of control on Thursday afternoon with eight vehicles responding.

Forest Fire Management Victoria said the fire was 1090 hectares in size but there was currently no threat to communities from fires in the region.

People should continue to stay informed and monitor conditions using http://emergency.vic.gov.au/.

READ MORE: Wimmera CFA volunteers join East Gippsland firefighting effort

Earlier: People in the Wimmera would be able to smell smoke on Thursday from fires contained in areas in the south west of the state, with smoke also an issue from fires in the Big Desert, the Country Fire Authority said.

"There are a few fires contained to the bush with control lines around them but a lot of that stuff is inaccessible, so it can't be completely put out," District 17 operations officer Alfred Mason said.

Mr Mason said the Henty Highway near Cherrypool was reopened to motorists on Wednesday afternoon and that crews were using infared thermal imaging cameras to check the fireground for activity.

Forest Fire Management Victoria said there was currently no threat to communities from fires in the region, but people should continue to stay informed and monitor conditions using http://emergency.vic.gov.au/.

Victoria Emergency said smoke could affect people's health and that if have difficulties people should seek medical advice from their doctor or call Nurse on Call on 1300 606 024.

READ MORE: Three patients admitted with heat-related health issues in the Wimmera

People with heart or lung conditions, such as asthma, children, pregnant women and older people were more sensitive to the effects of breathing in smoke.

Anyone experiencing wheezing, chest tightness and difficulty breathing should call Triple-0

A fire in Big Desert Wilderness Park and Big Desert State Forest was out of control on Thursday morning, while another two fires in the area had been contained.

Six vehicles have been responding to the out of control bushfire, which was 43 kilometres north north west of Yanac.

An advice message remained in place for Big Desert, Telopea Downs, Waggon Flat, Netherby, Yanac, Murrayville, Cowangie and Corina.

One of the bushfires has been contained on the eastern side of the Nhill-Murrayville Road and the southern boundary.

Forest Fire Management Victoria said emergency vehicles would be on the Nhill-Murrayville Road and advised people to use caution with smoke over the road reducing visibility.

The bushfire on the southern boundary of the Big Desert State Forest has also been contained.

An advice message was in place for Connewirricoo, Edenhope, Harrow, Kadnook, Wombelano with a bushfire at Kadnook in the Yallakar State Forest under control. The total size of the fire was 295 hectares.

There was also an advice message for Mafeking and Pomonal with a bushfire 13 kilometres south of Pomonal, in a remote area of the Grampians National Park under control.

Forest Fire Management said the small bush fire started from a band of lightning and was burning near Boundary Gap on the Major Mitchell Plateau.

Fire crews have been working in the area and there was no visible smoke.

Mount William Road was open to motorists on Thursday. The Major Mitchell Plateau walking track remained closed, while Mount William Summit and Kalymna Falls walking tracks were opened to hikers.

Further information about closures in the Grampians National Park could be accessed at www.parks.vic.gov.au/places-to-see/parks/grampians-national-park.

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