The NSW State Emergency Services (SES) will be using a new warning system from September 30.
Warnings will be issued using the new Australian Warning System (AWS), a national three-tiered warning framework which will cover all emergency services organisations across all hazards.
The warning system comprises of warning levels, action statements, hazard icons, colours and shapes.
There are three levels within the AWS - Advice, Watch and Act, and Emergency Warning.
For each level, there are a series of clear action statements to guide positive action by the community.
The three levels and their action statements are:
The NSW SES Hawkesbury Unit posted on its Facebook that: "With a third La Nina weather event, forecast for autumn and summer, it is a good time for our residents and businesses in the Hawkesbury, Colo and Macdonald Valleys to be prepared for flooding, become familiar with the new warning system; and discuss with your family, friends and work colleagues what you will do if or when you receive a warning".
Hawkesbury Mayor, Sarah McMahon, said Hawkesbury City Council were actively planning and preparing for the next floods.
"My message to the community is that you need to be prepared and you need to be educated on how floods behave, because you need to know what level your home and your property are," she said.
"You need to know what the heights of the previous floods were, you need to know how the Hawkesbury Nepean Valley Floodplain works.
"The information is out there for people to access it, especially from the NSW SES, and from Infrastructure and Water NSW, as to how dangerous our floodplain is.
"We really need people to go and source that information and be aware of it."
Warnings on floods and other emergencies will continue to be distributed through the NSW SES website, NSW SES social media channels and local ABC radio.
To learn more about the new Australian Warning System visit ses.nsw.gov.au/warnings.