East coast low set to smash NSW, bringing flooding, wild winds and high surf to coast

Heavy rain which could bring flooding, strong winds and large surf is set to hit Australia's east coast next week.

The wintery blast will bring gusts of up to 100km/h, forecasters say, with rainfall totals reaching 300mm possible in some areas, potentially causing flooding.

Weatherzone says the potential east coast low is developing off the northern NSW coast, and will deepen on Monday.

READ MORE: UK singer makes emotional return to iconic festival after health struggle

"Showers and fresh winds could intensify into heavy and potentially flooding rainfall, and damaging winds as the system develops into a potential ECL somewhere near the NSW coastline on Tuesday, July 1," Weatherzone forecasters said.

"Rainfall accumulations of 100-200mm are possible over a period of 36-48 hours to Thursday next week, across parts of the Mid North Coast and Hunter, possibly extending as far south as the South Coast.

"The deep feed of moisture coming off the Tasman Sea could interact with local topography around the Mid North Coast, Hunter and Central Coast, with rainfall totals reaching 300mm possible in some parts."

Waves of up to 13 metres are possible, it warned, with coastal erosion likely.

However, they say it's unclear how it will develop.

READ MORE: Funeral home owner who stashed nearly 190 decaying bodies sentenced to 20 years in prison

Rain is forecast in NSW from Monday afternoon until Thursday, the BOM reports.

It will get up to 17C in the day, with the sun set to return on Friday,

Other east coast lows which have smashed the coast have brought erosion to parts of Sydney's Northern Beaches and the NSW Central Coast.

READ MORE: Hepatitis A outbreak in several European countries

It once snowed in Sydney on this day

While Sydney is sunny with temperatures of between 18 C and a low of 6C overnight, it did once snow on this day.

In 1836, newspapers reported "the first snow storm ever known in Sydney."

According to a post on Instagram from City of Sydney, newspapers reported temperatures of just 3C.

It noted supplies were limited at markets because of the weather.

READ MORE: Security guard stabbed outside Woolworths

Weather forecast around Australia

Melbourne can expect showers from Sunday and into the week, with temperatures between 5C and 13 C.

Canberra can expect a chilly overnight temperature of -6 on Sunday, with highs of 13C.

Showers will clear by Monday in Adelaide which will get up to 16C.

Brisbane is also set for showers into the week, as is Perth.

Cairns will have a wet weekend but will be a warm 26C.

Hobart will be mainly sunny once showers ease on Sunday.

READ MORE: Man shot inside parked car in Sydney's west