Australia’s soggy summer is extending into autumn with significant rainfall driven by La Nina expected across NSW and Queensland in coming days.

It has already been a wet week for large parts of NSW, while there were emergency rescues in Queensland on Wednesday after record deluges overnight.

River heights in the town of Sapphire rose rapidly to above major flood levels on Wednesday, prompting a warning for residents to get to higher ground early on Wednesday morning.

Up to 215 millimetres fell into the Retreat Creek catchment, rapidly pushing the creek – which skirts the southern end of the Queensland Central Highlands town – to a major flood level.

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Central Highlands Regional Council disaster co-ordinator Glenn Bell said the SES had rescued a “number of people”. One person was rescued from the top of their car by another local about five kilometres out of town.

“The SES has been out and had to assist people from the roof of their houses,” Mr Bell said.

“We’ve had a number of people stranded in floodwaters who have also had to be rescued.”

Further north, a rain gauge just outside Rockhampton registered a record 550 millimetres of rain in 24 hours to Wednesday morning.

By the afternoon, the intense rainfall across Queensland had eased and river heights were dropping, but the Bureau of Meteorology (BOM) warned more thunderstorms were possible inland.

Farmers and graziers who missed out on predicted rain from this year’s La Niña event were thrilled after receiving widespread rainfall overnight.

Data from the BOM shows in the 24 hours to 9:00am Wednesday, Roma received 105 millimetres, while Forest Vale near Mitchell recorded 111mm.

Areas further south, including Dalby, recorded totals of about 24 millimetres.

Grazier Noel Chiconi said he had received 76mm of rain over the past two days at his property, Taylors Plains, about 100 kilometres north of Mungallala.

“We’re up to 250mm for March so far which puts us in front of our previous highest March total for the last 18 years,” Mr Chiconi said.

“It looks like a good season is coming up for us.”

The bureau also predicts more rain is on the way for other parts of Australia’s east.

“Rain, and bucketloads of it, is on the way for NSW,” forecaster Weatherzone said on Wednesday.

“The main question now is how much?”

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The weather bureau said rainfall that had hovered over north-western NSW would shift east on Wednesday and Thursday, showering the coast, Central Tableland and New England regions.

Meteorologist Helen Reid said the mid-north coast would be particularly affected in the next 48 hours.

“We do need to be mindful of the sodden river catchments in that part of the world,” she said.

Flood watches are current for the Orara, Bellinger and Nambucca rivers, and a severe weather warning has been issued for possible heavy rainfall for the entire mid-north coast district.

Thunderstorms are also possible in the NSW north-west as the week rolls on, but they will be milder than in recent days.

Sydney will also be wet, with rainfall increasing ahead of a damp weekend, Ms Reid said.

“Catchments further south, including the Hunter and down to Sydney and the Illawarra, we’re likely to be having flood watches issued for them as the system evolves,” she said.

However, the ACT would escape the worst, copping only a few showers, she said.

Driving the weather is the La Nina oscillation, which generally causes increased rainfall across much of country, cooler days in the south and warmer nights in the north.

“We still have the effects of a lot of moisture feeding into the system and that’s just helping us have a wet autumn following on after a wet summer,” Ms Reid said.

-with agencies