October records tumble in Qld hot spell

October temperature records have tumbled across parts of southern Queensland as the state continues to be gripped by a hot spell.

Four towns broke long-standing records for the hottest October day on Sunday, and those new records were broken again on Monday.

Goondiwindi hit 41.3C on Monday, Applethorpe got to 34.7C, Stanthorpe reached 35.5C, and residents in St George sweltered through a 42.6C afternoon.

Brisbane residents tolerated a 34C day, but it was nowhere near the October record of 40.7C.

The system driving the warm weather is a persistent trough sitting over inland Queensland, Bureau of Meteorology forecaster Janine Yuasa says.

"That's directing the warm dry air mass over, bringing it across from the interior of the continent to the southeast of the state," she told AAP on Tuesday.

The minimum temperature record was also rewritten on the Gold Coast, with the Coolangatta airport recording 29.1C at 3am (AEST) on Monday.

It was the warmest minimum temperature recorded at that time of the morning in 27 years, Ms Yuasa said.

Toowoomba recorded 22.8C on Monday morning, breaking the previous record for the minimum October temperature of 21.9C, which occurred on October 20, 2002.

The hot spell is expected to continue for the next few days, with high to very high fire danger warnings in place across much of the state.

A severe fire danger has been forecast for the Darling Downs and Granite Belt districts.

While afternoon storms delivered welcome relief, they also brought the threat of fires sparked by lightning strikes, the Rural Fire Service Queensland (RFSQ) warned.

High temperatures and low humidity are creating ideal conditions for fires to quickly spread, RFSQ assistant commissioner Neil Gallant say.

"These conditions also make it difficult to contain vegetation fires, so we're asking residents to take extra care and be alert."

A number of grassfires have kept firefighters busy on the Darling Downs, Granite Belt and Gold Coast hinterland.

Tim Coelli's winery, Twisted Gum, is perched high on a ridge near the town of Ballandean in Queensland's Southern Downs region.

He's lost about a hectare of chardonnay grapes - or about a third of his crop - to a bushfire that broke on Monday.

"Not substantial - we've got three hectares and most of our stocks of reds are luckily spared so we've got about three years' supply," he told the ABC.

QFRS Commissioner Lee Johnson said thunderstorms over southeast Queensland on Monday sparked about 18 fires, and the one at Ballandean is a major blaze.

"We're keeping a very, very close eye on that," he said.

Conditions eased on Tuesday, but he's repeated the warning for people to take extreme care amid the high fire danger and to report any fires.

"We need to get on top of these outbreaks in these types of weather conditions as absolutely, as quickly as we can to stop them becoming a major concern for us," Mr Johnson said.