The hail has decimated vegetation, cars and homes across the region.

State Emergency Service public officer Brent Hunter said within 15 minutes of the storm hitting Queanbeyan, they had 11 calls for help.

By 6pm, the Queanbeyan SES had 90 calls for assistance. 

Mr Hunter said each and every volunteer of the 100-strong group had been called in to help.

"We're looking at trees down, roof collapses, severe hail damage," he said.

"We will be here all night."

Residents were being urged to stay off the roads and undercover. 

Riverside Plaza has been evacuated following the following storm due to water damage. 

Caitlin Simpson from Pacific Smiles Dental said she had a patient in the chair at the time.

"She said a storm warning had been issued on the Bureau of Meteorology about 15 minutes before," Ms Simpson said.

"We got done and we started hearing this crashing on the roof... We all ran out and it was just hailing huge bits, huge bits. 

"It looked like it was snowing," she said.

Ms Simpson said the door of the dentist was "like a waterfall".

"The water was about an inch or two off the floor... water was pouring out of the light fixture."

It was not long after that security guards evacuated the building, Ms Simpson said.

Bureau of Meteorology forecaster Sarah Chadwick said the "supercell" storm was one of the larger ones throughout the district today.

"There are still some large thunderstoms about the Southern Ranges but none seem to be quite as large as the one that went through a short time ago," she said.

"That was the big one, but there are still some we would consider severe around."

She said the storms were moving moderately quickly, but were quite intense.

"We are probably going to see some more thunderstorms for tomorrow and we did have thunderstorm warnings out yesterday - so that's three days that we could potentially see storms for."

For help in storms, phone the SES on 132 500.