New South Wales Rural Fire Service (RSF) commented on Facebook: "If this rainfall forecast comes to fruition then this will be all of our, birthday, engagement, anniversary, wedding, and graduation presents rolled into one".
Temperatures above 40ºC and strong winds have made it more hard to fight the fires.
There is widespread anger in Australia over prime minister Scott Morrison's handling of the bushfire crisis.
They have been clearing vegetation and carrying out controlled burns in an effort to protect areas like the coastal town of Eden, where a large bushfire is burning to the south. However, New South Wales Rural Fire Service spokesperson Anthony Bradstreet warned that the rainfall is unlikely to put out all the fires.
Australian firefighters said Monday that the large "megafire" with an area of around 1.5 million acres, which formed along the border between the Australian states of Victoria and New South Wales last week, is finally under control.
The 60-year-old married father of two was praised in November for 40 years of service at the forest agency.
"All gathered gave a spontaneous & lengthy round of applause, reflecting the gratitude & admiration we all have for their generosity", Fitzsimmons said in his tweet.
At least 28 people have been killed in the fires that have destroyed 2,000 homes and razed 11.2 million hectares (27.7 million acres), almost half the area of the United Kingdom. Four of the victims were firefighters. Experts say that due to the attitude of the government on climate change, frequent and bad fires are taking place.
The Australian government has called the crisis "an ecological disaster", with critically endangered species hugely at risk.
Australia is generally hot and dry during the summer season, but due to climate change, the range of drought and heat has increased, so the bushes also dried up.
"This is a longer-term risk framework model which deals with one of the big issues in response to the climate changing", Morrison said. "This is obviously affected by the broader changes in climate", he said.
State authorities have said a minority of fires are deliberately lit.
In a TV interview with ABC, he said: 'These are sensitive environments.
The prime minister - a staunch supporter of fossil fuel industries - said emissions targets would "evolve" but ruled out curbing Australia's vast exports of coal.
"The government's policy is set by the Cabinet".
Glen Schlehuber, Tiffany & Co's vice president and managing director for Australia and New Zealand says the company has also donated to support firefighters and wildlife recovery.