A deluge of torrential rain hit SE Qld overnight, flooding parts of Brisbane, Ipswich and the Gold Coast and prompting Premier Anna Bligh to declare a state emergency.

A massive 243mm of rain lashed Tallegalla in near Ipswich overnight, with 208mm at Rosewood (including 110m in just one hour).

Other major falls were at Glenore (171mm), Gatton (164mm), Toowooomba (104mm) Enoggera Dam (96mm) and Carbrook (90mm).

Residents at Marburg, Rosewood, and Minden were evacuated.

Ms Bligh has been briefed on the extent of the damage by emergency authorities and has headed to the worst flooded areas of Ipswich this morning.

Part of the rail line between Ipswich and Brisbane has been washed out and services have been cancelled.

"It's like a wall of water washed through the city with cars washed off roads and very widespread flooding,'' Ipswich mayor Paul Pisasale said.

"Even if we knew the storm was coming, there was no drainage system in the world that could have coped with 250mm of rain."

The weather bureau has issued flood warnings for a number of rivers around the region, including the Bremer, Lockyer and Brisbane rivers.

Despite the devastation in the South East, good rain has also fallen overnight in rural Queensland.

There have been reports of more than 90mm west of Springsure on the Central Highlands, more than 75mm at The Caves north of Rockhampton, and between 25mm and 50mm at a number of points in between including the Callide and Dawson Valleys.

Another line of storms is set to develop at Charleville today and will progress east, but with less ferocity and without the support of an upper level.