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 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.
There were reports of cars and other people, including a mother with a pram, nearly being hit by several sheets of steel sheeting flying off a building site in the gale. Meanwhile, a Herald reporter narrowly missed loose plastic material landing on him near a construction site during the gust.
The National Parks and Wildlife Service has warned bushwalkers to delay their trips because of the weather. Weatherzone reported Sydney's temperature as being 13.2 degrees at 4.30pm on Monday, with a "feels like" temperature of 4.3 degrees.
Winds picked up about lunchtime with gusts in the city up to 90km/h and average wind speeds of about 60km/h at Sydney Airport.
Earlier on Monday, the Bureau of Meteorology issued a severe weather warning for "vigorous westerly winds" in the state's south-east in the afternoon, including for the Sydney metropolitan area, the Illawarra and parts of Hunter, South Coast, Central Tablelands, Southern Tablelands, South West Slopes and Snowy Mountains.
Bureau of Meteorology forecaster Zhi-Weng Chua said the worst winds, which gusted up to almost 90km/h about 1pm at the airport, had probably passed for the day in Sydney.
Mr Chua said wind speeds were expected to ease further on Monday evening but remain strong offshore and strengthen again on Tuesday and Wednesday.
"Tonight will be cold, or below average," Mr Chua said.
But slightly warmer minimum temperatures were expected for the weekend, he added.
The cold front also brought a dumping of snow to the Blue Mountains and Snowy Mountains overnight, with more falls expected during the week.
Perisher reported 20 centimetres of snow as the first blizzard of the season arrived.
The cold fronts bring to a screeching halt the near-record heat that has characterised most of the month so far.
The temperature at Observatory Hill in Sydney was just 13 degrees on Monday afternoon, according to Weatherzone, compared with a high of more than 27 degrees on Saturday.
That recording was more than 7 degrees above the average high for this time of year.
Last week, smoke haze choked Sydney, shrouding the city in a thick fog following hazard reduction burns by the NSW Rural Fire Service. Those conditions were caused by the combination of very light winds and a temperature inversion resulting from a high pressure system.
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