Margaret and Phillip Schwebel from Collins Booksellers said when the storm hit about 4pm on Thursday, they celebrated the rain until water started dripping from the roof.

"It was a case of be careful what you wish for," Mrs Schwebel said.

The water initially leaked into a jeweller on the second floor of Centrepoint Arcade before pooling on the floor and draining into Collins Booksellers and the hallway below.

"It was like a waterfall at one stage," Mr Schwebel said.

VIDEO: Water streams into the ground floor of Centrepoint Arcade....

Mrs Schwebel said when the water started to come through, two male customers "switched on" and helped the couple move books from the shelves to the back of the store, out of harm's way.

They estimated they lost a couple of hundred dollars-worth of books.

"If it had have been in the middle of the night, we would have lost thousands of dollars-worth of stock," Mrs Schwebel said.

Industrial driers were put in place overnight and the bookshop was closed on Friday morning while the shelves were restocked, however the couple anticipated they would reopen later in the day.

Gary Blowes, who manages the building, said the gutters overflowed during the storm, causing damage to the two tenancies, but plumbers and a hydrologist would be on site before more forecast rain on Monday.

"[Yesterday] I thought the whole thing was going to wash away, but it looks okay today," he said.

Best & Less also experienced some excitement on Thursday afternoon when the State Emergency Service had to be called to unblock a drain on Anson Street outside the store.

Store manager Kylie Hall said the store was sandbagged as a precaution, but the water did not make it over the threshold.

Orange SES unit commander Rob Stevens said crews responded to only two incidents on Thursday, the other being water inundation into a house in Casey Street.

"It was unusually quiet for that type of event - that would normally generate between 20 and 40 requests for assistance," he said.

Possible rain and thunderstorms have been forecast every day until Monday.

Mr Stevens said the unit was ready to respond to callouts, plus four members were on standby to help with evacuations or logistics in relation to the bushfires and a swift water rescue strike team from the region was prepared to head to Gunnedah and Tamworth in case flooding occurred.

"Because it's been so dry for so long, everything's dirt, there's very little vegetation to hold the topsoil so the water won't sink in as fast and everything that drops will be straight runoff," he said.

Minimal rain is expected on Saturday, however between 20 and 40 millimetres have been predicted on Sunday and a further 10-20 millimetres on Monday.

Temperatures will remain in the low 20s, with a top of 26 degrees expected on Sunday.