A stretch of coastal NSW is on alert as wild weather sweeps in, bringing heavy rain, strong winds and freezing temperatures.

From Wednesday, parts of the east coast have been bracing for a “rain bomb” with falls expected to intensify and become more widespread over the next few days.

WATCH THE VIDEO ABOVE: Sydney braces for heavy downpour.

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“It’s going to be an extremely wet weekend, unfortunately, across the east coast of the state,” Bureau of Meteorology meteorologist Angus Hines told The Morning Show.

He said the worst of the rain will arrive early Saturday morning, pushing in from the northeast and lingering for about 24 hours until early Sunday.

While most areas from Coffs Harbour to Wollongong will be affected, the Mid-North Coast and Hunter region are tipped to cop the heaviest falls.

Falls of more than 100mm are highly likely along parts of the coast and adjacent inland to the ranges, according to meteorologist Jane Bunn.

That has raised fears of renewed flooding in regions hit earlier this year.

The wild weather has come with a cold snap, too.

Sydney recorded its coldest day of the year on Wednesday, with the city reaching just 12.5C.

Some suburbs barely climbed above 10C, and a few spots had their coldest day in four or five years.

And the chill is set to stay.

Hines said temperatures would remain below average for the next few days, with daytime highs likely to hover around 14C to 16C, though not quite as cold as the frigid conditions recorded on Wednesday.

Strong wind warnings are also in place for most of the NSW coastline, including Sydney’s beaches and harbours, as dangerous gusts move in.

“It’s going to be windy, it’s going to be raining,” Hines warned.

“So, for anyone who actually has to spend a bit of time outdoors, really rug up because it’s probably going to feel more like 11C or 12C.”

Showers are expected to linger into Monday and possibly Tuesday.

The next likely day with more sun than gloom appears to be Wednesday next week, Hines predicted.

Conditions are expected to ease early in the week as a high-pressure system settles in, blocking the next major system from reaching the east coast.

But more rain could be on the way from mid-next week, with another burst of tropical moisture from the Indian Ocean likely to develop, Bunn said.