Damaging winds that caused gusts of up to 90km/h in Sydney's CBD and up to 125km/h in the regions on Monday are likely to return on Tuesday in association with a new cold front, the Bureau of Meteorology has warned, after Sydney's seemingly endless summer came to an abrupt end.

In Sydney, winds whipping through the CBD and dubbed a "polar jet" by Weatherzone forecaster Andrew Miskelly, sent debris flying, causing problems for traffic and pedestrians alike while other areas of the state received a dusting of snow.

A poster is blown off a traffic light pole and pedestrians shield their faces as strong winds hit Sydney. Credit:Ben Grubb

A man was killed at Silverdale in Sydney's west when a flying branch hit a truck about 1.50pm, causing it to lose control before hitting a tree. The driver of the truck was flown to Nepean Hospital in a stable condition, but his passenger died at the scene.

A lane also had to be closed on the Sydney Harbour Bridge due to a loose sign, while fallen wires closed Seven Hills Road in Seven Hills.