One man has been killed and thousands have been urged to flee their homes in the midst of flash flooding and torrential rains in Sydney, Australia’s largest city.

Roads are now closed, with 18 evacuation orders for western Sydney and warnings about more.

Stephanie Cooke, minister for emergency services in New South Wales said that it was a life-threatening emergency situation.

Flash flooding killed 20 people in the area during March.

Ms. Cooke stated that “we are facing dangers from multiple fronts” during a media briefing.

The Bureau of Meteorology warned her that up to 350mm of rainfall had fallen in certain areas. This could lead to flooding of the Nepean River.

The main dam at Sydney had also begun to leak overnight, posing a concern for authorities.

Ms. Cooke stated that this was a rapidly changing situation and advised people to be prepared to evacuate as soon as possible.

She stated that there had been 83 flood rescues performed by emergency services within the last 24 hours.

Ms. Cooke stated that “it unfortunately shows that people don’t necessarily heed the advice we continue to provide multiple times per day in relation to flooding event.”

“I respectfully ask people to refrain from non-essential travel at the moment.”

The warnings came as an unnamed man died after falling from a kayak along the Parramatta River in west Sydney. After a member of public saw him struggling in the water, emergency officials tried to revive him but he died on the spot.

Experts believe that climate change and the La Nina weather phenomenon have contributed to the current flooding crisis. When strong winds blow warm Pacific waters away from South America towards Indonesia, a La Nina is formed. They are replaced by colder water at the surface.

A La Nina in Australia increases the chance of rain, cyclones, and cooler daytime temperatures.