Police say the 52-year-old man’s body was found on Tuesday hours after he disappeared when his boat overturned in floodwaters while he was looking for stock with two female family members near Tiaro, south of Gympie.

His two family members made it to safety, but the man became the second person to die in the floods caused by remnants of Cyclone Seth dumping torrential rain on the region.

“Queensland Police can confirm the body of a man who went missing in flood waters near Tiaro earlier today has been located,” they said in a statement.

The body of a 22-year-old was found in a submerged ute on Saturday, while police hold “grave fears” for a 14-year-old girl who has been missing for three days.

Police Commissioner Katarina Carroll, speaking in Maryborough on Tuesday in the wake of flooding in the region and throughout the Wide Bay region, warned against entering floodwaters.

Premier Annastacia Palaszczuk, also in Maryborough, announced that former Governor, Paul de Jersey, would lead the city’s flood recovery effort.

Palaszczuk siad 50 businesses had been impacted and 31 residences by the deluge of 650mm in a 24-hour period.

But as floodwaters slowly recede around the South Burnett, three people have been rushed to hospital after their vehicle was caught in floodwaters triggered by Cyclone Tiffany in far north Queensland.

Queensland Ambulance Service says two women in their 30s and a man in his 20s were driving on the Mulligan Hwy at Desailly, northwest of Cairns, when their vehicle was swamped about 1.30am on Tuesday.

The three managed to exit the vehicle and were found clinging to a tree, before they were transported to Mareeba Hospital in stable conditions.

Tiffany was a category two cyclone packing winds of up to 130km/h when it crossed the coast of the Cape York Peninsula on Monday afternoon.

Tiffany, which has weakened to a tropical low, dumped 120mm of rain in some areas in the 24 hours to 9am on Monday.

However, the Bureau of Meteorology said the heaviest rainfall would be in the 24 hours to midday on Tuesday with up 200mm to be dumped on the region.

A flood watch has been issued for 16 rivers in the region and Cape York’s major land transport route, the Peninsula Development Rd, was likely to be shut.

“Riverine and localised flooding is likely, causing disruption to transport routes and isolation of some communities,” the BOM said in a statement.

The remnants of Tiffany were moving west over the Gulf of Carpentaria on Tuesday morning and were forecast to intensify into a category two cyclone before hitting the east coast of the Northern Territory on Wednesday.

A 14-year-old girl swept away in floodwaters north of Brisbane has been missing for more than three days as Wide Bay residents assess the damage after a weekend of extreme weather.

Krystal Cain was swept away after abandoning a car caught in a flash flood on Friday night triggered when the remnants of cyclone Seth dumped more than half a metre of rain on the region.

A 40-year-old man who was with her was found alive more than 12 hours later clinging to a tree, but the teenager is still missing.

Police hold “grave concerns” for Krystal and a GoFundMe page has been set up by relative Aundreau Cain to aid the search effort.

“Krystal is a loving daughter, sister, granddaughter, niece and friend with an incredible talent to sketch all things animal,” Ms Cain wrote.

“She was swept away in a torrent of water whilst travelling to Agnes Water to see her grandparents. Krystal is still missing and we hold hope that she is still alive somewhere.”

The Police Commissioner said the search for Krystal was continuing however police are getting advice on “survivability” in the conditions.

Water police, divers, volunteers and helicopters are assisting with the search, and Prime Minister Scott Morrison on Monday said his thoughts are with the girl’s family.

“I have a daughter who’s 14 years old, so I can understand the terrible, terrible time that family must be going through at the moment,” he told reporters.

The prime minister also gave his condolences to the family of a 22-year-old man whose body was found in a submerged ute at Kanigan, north of Gympie, on Saturday.

There is still major flooding across the Mary River catchment on Tuesday morning, but water levels dropping in Maryborough.

A flood levee was in place when the river peaked at 9.96m on Monday night, but the CBD still flooded after an underground stormwater valve failed on Sunday, allowing water to surge up through the drains.

Queensland Fire and Emergency Services Minister Mark Ryan said up to 80 homes and 70 businesses in Maryborough have been flooded.

“Unfortunately, we have already seen people lose their lives in floodwaters and it’s a tragic reminder to all Queenslanders that if it’s flooded, forget it,” he said in a statement.

“Queensland’s emergency services staff continue to work around the clock in response to the ex-Tropical Cyclone Seth flooding and we will assist all impacted councils and communities.”

Police said an emergency declaration for Maryborough is due to be reviewed on Tuesday morning.

“Members of the public are asked to stay away from flood-impacted areas due to potential hazards generated by the flood waters,” police said in a statement.

Wide Bay-Burnett region residents affected by the disaster will be able to access disaster grants of $180 for individuals and up to $900 for a family of five funding by the state and federal governments.

Federal Emergency Management Minister Bridget McKenzie said jointly funding low-interest loans of up $250,000 will be available for primary producers and small businesses impacted by the floods.

“This event is still unfolding, but we already know that the severe flooding has tragically resulted in the loss of life, in people being evacuated from their homes, and in significant damage to roads, bridges and other infrastructure,” she said in a statement.

“Fraser Coast and Gympie are at the centre of this unfolding emergency, with homes and business already submerged.

The bureau has issued a cyclone warning for the Territory’s west coast from Nhulunbuy to the Queensland border, including the island of Groote Eylandt, Numbulwar, Port Roper, and Port McArthur.

People in coastal areas between Cape Shield and Nathan River are being warned that gales could develop into destructive winds with gusts of up to 140km/h on Wednesday morning.

The BOM said people as far west as Barunga and Mataranka may experience gales of up to 100km/h with heavy rain expected to cause flooding across the Arnhem and Carpentaria districts as the cyclone moves inland.