A brief return to chilly weather is on its way to southeastern Australia, with Tasmania and parts of the mainland in line for a wild, windy, very wintry Tuesday.

We wrote last week about the spring temperature "see-saw", and the temperature contrasts will be stark in the first few days of this week across Australia's most populated corner.

Melbourne's maximum will drop from around 19°C this Monday to around 14°C on Tuesday and just 13°C on Wednesday. The average September maximum is 17.3°C.

Hobart's maximum should reach around 21°C this Monday but peak only around 13°C on Tuesday. The average September maximum is 15.2°C 

Sydney's maximum will drop from around 26°C this Monday to around 18°C on Wednesday. The average September maximum is 20.2°C.

Canberra is set for a mild 21°C this Monday but by Wednesday the mercury should only peak around 13°C, followed by a frosty start to Thursday. The national capital's average September maximum is 17.9°C.

Light showers and mountain snowfalls on the southern mainland

This will not be a particularly wet system for the mainland, with only a few showers likely in southern Victoria, with light snowfalls in the high country of Vic and southern NSW.

Tuesday's snow level of 800 metres above sea level for this region emphasises how chilly the coming air mass will be. Unfortunately, any snowfalls won't mean much for the ski resorts, as only Perisher in NSW remains open.

Widespread Tasmanian rain and showers with snow to low levels

For Tasmania, it's a different story with showers extending across much of the state on Tuesday, heaviest on the west coast.

The BoM has forecast a Tuesday snow level of just 300 metres across parts of the state. This would be a very low level for midwinter and is as low as any Tasmanian snow level forecast to date in 2026.

Image: Forecast accumulated rainfall totals to 10 am (AEST) on Thursday, September 17, 2026, for SE Australia, according to the ECMWF model. Source: Weatherzone.

Windy weather to spread up east coast

After the cold front crosses Tasmania and the southeast tip of the mainland, it will push northwards over the Tasman Sea, with powerful winds lashing the coast and adjacent areas.

Numerous wind warnings are already in place across the southeast as gusty northwesterlies ahead of the cold front increase in intensity this Monday, while multiple coastal wind warnings for gales and strong winds have also been issued for Tuesday, with more likely to follow.

A gust of 104 km/h was recorded at Australia's highest weather station, Thredbo Top Station, just before 5 am this morning, while the notoriously windy Maatsuyker Island on Tasmania's southwest tip recorded a gust of 109 km/h just after midday on Monday.

Please check the Weatherzone warnings page for all the latest severe weather warnings.