The bush fire north of Cooma has been upgraded to out of control status and firefighters have been defending a number of properties as hot winds create spot fires.

A southerly wind was expected to push smoke from the fire – burning near Shannons Flat Road since Friday - across parts of the ACT from Monday night.

Smoke has been visible from Cooma and the Monaro Highway.

An ACT strike team of 28 people departed for the fire early on Monday, with 73 firefighters battling the fire,  which has burnt about 1500 hectares.

NSW Police doorknocked in the small Mt Oak community to warn of the need for preparation, as south-westerly winds pushed smoke and embers towards the town.

A NSW Rural Fire Service spokeswoman said the fire had been upgraded to out of control at 1pm after hot westerly winds created spot fires.

A number of farmhouses were defended, as temperatures hit 37 degrees at Cooma airport, with wind gusts of up to 37 kilometres per hour.

“The crews this afternoon were engaged in property protection … [there’s] no reported property losses,” the spokeswoman said.

“At this stage there’s no direct threat to property.

“The large majority is forest [fire]. There was a bit of a grass fire today, but that was contained quickly.”

Cooler conditions on Tuesday are expected to help control the fire, with a top of 22 degrees tipped for Cooma.

“There’s a low to moderate fire danger rating [for Tuesday],” the spokeswoman said.

“Winds of around 20-30km; east-south-easterly winds.”

The alert level on Monday night was Watch and Act.