However the wetter-than-normal spring heightens the risk of grass fires, a new report warns.

In its outlook for September to November, the Bushfire and Natural Hazards Cooperative Research Centre said large parts of eastern and northern Australia were expecting wetter than average conditions through spring, with a 70 per cent chance of a La Nina forming in 2020. This is around three times the normal likelihood.

There's also a possibility of a half negative Indian Ocean Dipole developing during spring, which would further increase the likelihood of wetter than average conditions across eastern Australia.

This means south-eastern Australia are facing "normal" fire potential.

In the ACT, rainfall in early August was enough to ease the threat the residual drought poses for a higher-than-normal risk of forest fires this coming fire season.

With more rain on the way, it is likely the forest flammability will remain low in the territory over the coming months.

This is remarkably different to the conditions at the same time last year.

Last August, the centre warned the east coast of Queensland, NSW, Victoria and Tasmania, as well as parts of southern Western Australia and South Australia, faced above normal fire potential.

The ACT had received below-average rainfall for the preceding two years, with the persistent drought leading to a high risk of fires in lowland forests, the centre said at the time.

In NSW, 55 per cent of the state was drought-affected, 17 per cent in intense drought. Widespread dry conditions led to an early start to the fire danger period in many local government areas.

But steady rainfall across NSW over the past six months has increased moisture in the soil across much of the state, decreasing the risk of bushfires.

However north and west of the state are still experiencing dry conditions, especially in the northern ranges. Parts of Queensland also face above-average fire conditions, despite the elevated rainfall.

But while the rain has brought some welcome relief, it also poses a new risk.

The centre warned the rain, combined with warmer than normal temperatures, had the potential to increase grass and crop fuel loads.

As this dried coming into summer, it could increase the risk of grass fires across NSW.

"Higher grass fuel loads can increase fire danger by increasing the intensity of grass fires. All other factors being equal, this increase of the intensity makes the grass fires hotter, more dangerous and harder to extinguish," the centre said.

In the ACT, the impact of the rain on the risk of grass fires would not become clear until the end of spring or early summer.

"These conditions will be monitored over the coming months," the centre said.