A broad and unpredictable trough stretching across south-east Australia could inundate Canberra with a month's worth of rain this weekend.

Temperatures are set to climb towards 40 degrees in coming days in Sydney's west with only cooling sea breezes likely to cap the mercury in the city.

Parts of Canberra have received more than the city's June average rainfall in less than two days with more rain on the way.

The impacts of the monster El Nino in the Pacific are likely to intensify across much of Australia, including worsening drought and an elevated bushfire threat, after conditions that were nullifying its effects suddenly retreated.

A "strangely warm southerly" is sweeping across Sydney today with little relief from the heat at beaches in NSW and Queensland because of Cyclone Winston causing large, dangerous and powerful surf.

Destruction of more than 200,000 hectares of threatened species habitat has been approved by the federal government in the past decade, a report shows.

Broken Hill's water reserves are down to about 4 per cent amid forecasts the town will be without water by the end of the year.

The state's second east coast low in as many weeks is likely to bring further heavy rains to north-eastern NSW but largely skirt flood-hit areas around Sydney and the Hunter Valley, meteorologists say.

Fires breached containment lines in two NSW locations on Sunday morning as temperatures climbed above 35 degrees in parts of the state and Sydney.

A car reportedly crashed into a fallen tree on Streeton Drive. 

Winter's grip will finally feel like it's loosened amid a "heat spike" this weekend - even if that season's squeeze was not a very tight one.

Hundreds of homes have been evacuated in southern California as heavy rains and wind lash the drought-stricken area.

Santa looks set to bring Melburnians a mild and mostly sunny Christmas Day.

"Mate, I lost about 100 heartbeats I reckon in that split second, and got a few more grey hairs."

Slow-moving Typhoon Hagupit has weakened as it churns across the central Philippines islands, easing fears of widespread mass destruction, but officials warn the storm could still bring severe flooding to the low-lying capital Manila.

It's Big Wednesday in Sydney, where large and powerful waves are pounding the coastline and giving surfers a reason to grin.

NSW will likely cop its third buffeting from an east coast low in five weeks but there is some good news.

Canberra hasn't seen any heatwaves this summer, but that doesn't mean it hasn't been a hot one.

The Bureau of Meteorology has warned of possible flash flooding in the Queanbeyan and Molonglo rivers on Friday.

While the dry,calm, and mostly sunny days are making it seem that summer will never end, its demise is in sight.

Brisbane is in for a wet start to the week, with storms likely to hit the city on Monday and rain predicted for the following four days.

Australia's main ski resorts are anxious for a change in the weather, with a lack of recent snow falls limiting their operations just as school holidays loom in NSW and Victoria.

A Kiama drone operator has told of his urgent efforts to raise the alarm after a shark made an unexpected appearance in his video, coming disturbingly close to unaware surfers.

Prepare for hotter days and a worsening drought - a ''substantial'' El Nino event is underway.

Sydney's run of unusually cold mornings will extend well into next week as mostly clear skies combine with light winds and a frigid air mass to sink the mercury.