Tens of thousands of Sydney residents have been left without electricity after 43 outages swept across the network on Saturday, with nearly 40,000 customers affected, according to Ausgrid.

The worst‑hit pockets stretch across the city’s south‑west, with nearly 20,000 residents in Picnic Point, Panania, Padstow, Revesby and East Hills reporting sudden blackouts as crews work to stabilise the grid.

Ausgrid says field teams are already on site across multiple suburbs to investigate the cause and begin restoration work, but warned some areas may face extended delays as damage assessments continue.

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Power is expected to be restored later on Saturday night.

Saturday’s outages follow a warm, windy afternoon in Sydney, with gusts strong enough to bring down trees and branches across several suburbs with the SES issuing a severe weather alert.

A severe weather alert has been issued for Sydney Credit: SES

Sydney’s south-west is one of the worst hit areas. Credit: Ausgrid

Emergency services responded to dozens of calls for fallen vegetation, with crews clearing debris from roads, footpaths and powerlines.

“Police are aware of significant weather affecting much of the Blue Mountains and Western Sydney areas,” the NSW police force said on Facebook.

Authorities are urging people to stay clear of fallen lines, treat all damaged infrastructure as live, and follow updates through Ausgrid’s outage map.