Early spring fire bans have been put in place as Australia’s eastern states reckon with unseasonably hot conditions for the start of the season.

The Bureau of Meteorology (BoM) warned of unseasonal heat in the low to mid-30s in north-eastern New South Wales and south-east Queensland.

Brisbane had a forecast top of 34C, while Sydney had some respite from the recent record temperatures, with a forecast top of 23C, as that heat moved north.

If Brisbane reaches its predicted temperature peak, it would be the hottest September day in the city since 2019. Brisbane recorded a temperature of 31.6C in the late morning, the weather bureau said, while the Ipswich suburb of Amberley recorded a peak of 35.7C in the early afternoon.

“It’s a bit of an ‘all eyes on the temperatures this afternoon’ type [of] thing until that south-easterly change gets in, which is probably about 6 or 7pm tonight,” the BoM’s Steve Hadley said.

The Queensland fire department has issued local fire bans for Ipswich and the Lockyer Valley as the state comes close to shattering records for the highest temperatures seen in early September.

Areas from Gladstone to the Gold Coast were likely to come a few degrees shy of breaking the record for the state’s highest recorded temperatures for the start of spring.

The state had experienced its third-warmest winter on record with temperatures 1.8C above the long-term average.

BoM meteorologist Jonathan How said over the past 24 hours, a cold front swept across south-eastern Australia bringing damaging winds, rain and storms.

“At the same time, parts of eastern NSW saw their warmest early spring day on record,” he said.

But a dry cool change was moving up the east coast, bringing milder temperatures from Monday. Western Australia is set to get more rain this week, while Tasmania and Victoria can expect some showers.

South-east Queensland’s fire bans came a day after a similar ban was issued for the greater Sydney region, with early spring temperatures climbing to 33C on Saturday in the NSW capital.

Maximum temperatures across the city during the first days of September matched the midsummer average of 26.4C, warmer than any other start to spring since observations began.

Severe weather warnings were in place for south-eastern Australia over the weekend as damaging winds fuelled the hot conditions.

Jumping castles were picked up by strong winds in two separate incidents in NSW and Victoria on Saturday.

Two children were treated for head injuries at a scene in Banksia, in Sydney’s south, before being transported to hospital.

An infant with minor injuries was also hospitalised, while a woman was treated at the scene.

Two children in Mount Duneed, near Geelong in Victoria’s south-west, were hospitalised after the jumping castle they were using was lifted into the air.

Temperatures are expected to drop in the coming days across both NSW and Queensland.