The weather bureau says above-average temperatures will hang around for "the foreseeable future", with a warm air mass above most of Queensland showing no signs of moving on.

The gloomy forecast comes after the central Queensland town of Blackall dropped to 30.7 degrees overnight, its warmest night on record, and the outback town of Winton broke its February record for the highest minimum temperature at 31.3 degrees, according to the Bureau of Meteorology.

Brisbane only reached 33 degrees on Tuesday, two degrees below the forecast maximum, and residents woke to humidity above 80 per cent.

However, the river city was bracing for a top of 36 on Wednesday before temperatures were expected to cool down slightly, with an expected high of 34 on Thursday and 32 on Friday.

Elsewhere, Gatton was predicted to climb to 41 degrees on Wednesday and parts of the Darling Downs as well as the Wide Bay Burnett region were also expected to break the 40-degree barrier.