Police have launched a search for two men feared missing in flood waters in northern Queensland as the heavy deluge has authorities warning of more unpredictable and dangerous conditions over the next 24 hours.

A precautionary water and land search of the floods in Townsville, namely in the Aitkenvale area, has began for Hughie Morton, 21, and Troy Mathieson, 23, who were last seen on Ross River Road, on Monday morning.

There are concerns among Townsville police that the pair were swept away after hundreds of homes were inundated by water due to the opening of the Ross River Dam spillway gates on Monday.  

Extensive enquiries on Monday with family and friends failed to locate the men.

Police say anyone who may have seen them or has any information in relation to their current whereabouts can contact Policelink on 131 444. Photo: Channel 7

An emergency alert was issued for Bluewater, Bluewater Park, Toolakea and Saunders Beach, northeast of Townsville, early on Tuesday morning. Residents were advised to move to higher ground.

While about 1000 people remain in six evacuation centres, some residents are refusing to leave their homes.

Andrew Roberts says he and his wife, Cass, have food, water, and a radio and won’t be evacuating their two-storey home of 14 years in Hermit Park.

“It’s a little bit scary because when it floods in Townsville, the crocs get into the water,” Mr Roberts said.

“My biggest concern is getting eaten.”

Townsville remains the hardest-hit area although floodwaters are affecting communities as far west as Mt Isa, in the state’s interior.

The one-in-100-year deluge has caused catastrophic flooding as rivers and creeks burst their banks, spilling water through streets and consuming entire suburbs.

The vigorous monsoon trough dumping the rain has begun moving south.

Late on Monday, a severe weather warning remained in place from Ingham to Mackay, and west to Cloncurry, although lower than expected rainfall throughout Monday has eased conditions in Townsville.

Water levels in the Ross River Dam dropped to 211 per cent of capacity, down from 250 per cent earlier in the day.

Further heavy rainfall is likely to develop in the severe warning area on Tuesday, however, with six-hourly rainfall totals of between 150mm and 200mm possible, the Bureau of Meteorology said.

“Mackay could get some heavy falls over the next few days with some possibility of flooding,” meteorologist Jess Gardner said.

Inland, the rains have brought “tears of happiness” to the parched outback, where drought conditions had brought many graziers to their knees.

Dry rivers are again flowing where a week ago, it was just dust, Cloncurry Mayor Greg Campbell said.

“It is a great relief to the community. The old timers always say the only way to break a drought is with a flood,” he said.

-with AAP