UPDATE: Predicted heavy rain has arrived again in Toowoomba.
Outlying roads have been cut and one down lane on the Toowoomba Range has been closed to allow road crews to repair minor landslides.
Water authorities are tipping that Perseverance Dam will overflow late this afternoon - for the first ttime in about 10 years.
The Bureau of Meteorology earlier issued a severe weather warning for the south-east Coast, Wide Bay and Burnett districts.
It is predicting heavy rainfall leading to localised flash flooding and potentially worsening the existing river flood situation.
It comes after widespread flash flooding caught out inner-city retailers and motorists yesterday.
The storm dumped up to 60 millimetres in some parts of Toowoomba's CBD in the brief deluge about 9.30am.
Dent Street turned into a river, prompting Toowoomba Regional Council crews to close the street near Grand Central shopping centre.
West Creek behind Milne Bay Aquatic Centre became a raging torrent and captured the imagination of nearby business owners.
“We would be under water if this wasn't here,” Bill Stewart of A1 Fire and Safety store said of the elevated creek walls.
“It is an amazing sight.”
Grand Central centre manager Shaine Beveridge said water entered the entry foyer to Myer on the corner of Margaret and Dent streets.
“Some minor maintenance works will be required to restore the landscaping outside the Myer entrance where water washed away the mulch,” Mr Beveridge said.
Nearby at the Toowoomba City Bowls Club, Bruce Wright watched as the greens turned to swimming pools.
“They drain fairly well,” the greenskeeper said.
“But, in prolonged wet weather you do get a bit of algal build-up.”
Mr Wright, however, expected games to be played on the weekend, if the weather held out.
Water was also spotted over the road in Bridge Street, at the James and Kitchener street intersection, West Street near Drayton Road, Mackenzie Street near South Street and also Alderley Street.