"It's a similar stubborn pattern" that has persisted for some time, Robyn Duell, acting manager of the bureau's long-range forecasting service, said.

Loading

"It's not likely we're going to see respite" in regions where farmers have been seeing drought and where fire risks have been elevated.

More than 800 firefighters were deployed in NSW on Wednesday and there were still 79 fires burning - 36 of them yet to be contained - as of Thursday morning. Four Rural Fire Service volunteers were injured when a tanker rolled near Taree overnight, leaving one of them with suspected spinal injuries, the agency said.

A dry spring for eastern Australia would follow what's likely to be the driest first eight months of the year for NSW since 1965. Parts of Queensland are also exceptionally dry.

The outlook, though, points to Victoria and south-eastern South Australia facing the highest odds of abnormally low spring rain, suggesting the drought will continue to spread south.

"I don't want to get more negative but I'm not seeing anything pushing for an increase in rain," Craig McIntosh, a meteorologist with Weatherzone, said. "It's more like the other way."

Daytime temperatures are expected to be above-average for most of the nation each month in spring.

"At this time of year, [such conditions] increase evaporation and exacerbate dry periods," Ms Duell said. "It's been an unusually dry winter, and obviously this [forecast] is not what you want."

Dominant high pressure systems over the continent have pushed rain-bearing cold fronts southwards, and climate influences in the Indian Ocean or the Pacific continue to favour below-average rain.

Cooler-than-average waters off the north-west coast of Australia are "the strongest influence in this outlook", Ms Duell said.

At present, the bureau is rating the chance of an El Nino event in the Pacific later this year as double the normal odds, or a 50-50 prospect. That tilt is already a feature of the spring outlook and confirmation of an El Nino would add to the likelihood that the current dry conditions in eastern Australia have a way to go.