A wintry blast is set to snap south-east Aussies out of spring conditions with warnings of large hail and damaging winds to end the working week.
The Bureau of Meteorology has issued severe weather warnings for parts of NSW, the ACT and Victoria as a "powerful" cold front sweeps in on September 7.
"It's been pretty mild through winter but this is going to be a cold one," senior meteorologist Angus Hines said.
Severe storms with strong winds and large hail are possible as the front moves towards the east coast of NSW on Thursday evening.
"We could see wind gusts of 90 to 100 km/h through [warning] areas on Thursday," Mr Hines said.
"Victoria, Tasmania and southern NSW are going to see chilly conditions, further showers and the possibility of some fairly extensive hail come Friday."
Extensive snow is set to fall on Friday and Saturday with the lowest expected at 500 metres in Tasmania, 700 metres in Victoria and 800 or 900 metres in NSW.
After days above 20 degrees to start spring, inland temperatures are set to plummet on Friday into the weekend.
Canberra's sunny 23 degrees on Thursday will be followed with showers and a forecast top of 12 degrees on Friday.
IN OTHER NEWS:
Severe weather warnings issued for NSW, ACT and Victoria
A severe weather warning for damaging winds averaging 60 to 70 km/h, with peak gusts of about 100 km/h, is in place across western inland NSW, from Tibooburra and Bourke down to Griffith and West Wyalong.
A further warning has been issued for alpine areas where damaging wind gusts in excess of 125 km/h are likely to develop above 1900m on Thursday evening.
In Victoria, warnings for damaging winds stretch across the state including the Otways, Grampians and central ranges, as well as the outer northern suburbs of Melbourne.
The State Emergency Service advises people should move vehicles under cover or away from trees and secure loose items on their property.
Marine wind warnings are also active for September 7 and 8 on coastlines across south-east Australia.
Stay up-to-date with weather warnings at bom.gov.au/australia/warnings