Forty-eight trucks from across the zone from Young, Boorowa, Harden, Cootamundra, Gundagai and all places in between responded to help battle the blaze, at its peak soon after dark.

The crews were tasked to the northern edge of the 337,035 hectare bushfire at Ellerslie Nature Reserve near Mount Adrah, as it bared down on Tumblong and put Gundagai on alert for ember attacks.

The day began with 14 of the zone's appliances on deck, however support was soon needed when the change occurred about 2pm.

As conditions deteriorated into the evening, a further three pre-planned Strike Teams from units right across the zone were deployed.

Zone district manager Tom McDevitt said it was some of the worst fire conditions local crews have faced this season, since beginning deployments to northern parts of the state in August.

"We've seen some horrific days [since August]. Friday evening was equal too or greater," Mr McDevitt said.

Since the Dunns Road fire commenced, the SWS RFS zone has been supplying up to 16 trucks at a time over a 24 hour period, mostly being deployed to its northern edge.

It's expected the zone's units will continue this effort for at least the coming 10 days.

"From a manager's perspective, the volunteers have been very supportive to the firefighting efforts. So much so that the fire control centre hasn't had to put the call out. Brigades are coming to us to assist," Mr McDevitt said.

"I think it's a sense of community and a sense of loss as well. A lot of our volunteers are landholders and their feeling for their counterparts.

"I can't praise the volunteers enough. Many are putting in long days and multiple days of firefighting, they're having a red hot crack.. they're going above and beyond."

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