* The current drought is one of the worst in the past century.

* Autumn in 2018 was the fourth-warmest autumn on record, with rainfall totals below average for most of Australia.

* Last month was also the driest July nationally since 2002.

* In NSW, drought is affecting roughly 99 per cent of the state, with the Western, North West, Northern Tablelands, Hunter, Central West, Central Tablelands, Riverina and South East regions hardest hit.

* About 58 per cent of Queensland is in drought, with producer group AgForce saying parts of the state's west and south have been drought-affected for more than six years.

* Along with parts of NSW and Queensland, rainfall deficiencies deepened in July in northern Victoria, eastern pastoral and southern agricultural regions of SA and southern WA and its Gascoyne coast.

* On top of the dry conditions, there is a 50 per cent chance of an El Nino weather event developing in spring 2018, which is linked with below average rainfall in Australia's southeast.

Australian Associated Press