Rivett, Forrest, Griffith, Narrabundah and Queanbeyan were among the suburbs affected by power outages.

Queanbeyan and surrounding areas were the worst affected, with most of the area left in the dark from shortly after 8.45pm.

Power was restored to most customers before 11pm.

According to the Bureau of Meteorology more than 31mm of rain fell on Canberra from 8.40pm to midnight.

The ACT State Emergency Service received 42 requests for assistance.

The majority of requests were received from Civic, Braddon and Dickson in relation to minor roof damage, fallen trees across roads and local flooding issues.

More than 1500 people were evacuated from the Canberra Theatre Centre and left standing in the rain due to a fire alarm shortly after 9pm.

The crowd had been watching Ru Paul's Drag Race tour when firefighters were called.

Andrew Brown, a reporter with the Sunday Canberra Times, was at the show and said: "There was the smell of smoke in the auditorium and everyone has been evacuated out.

"Everyone is scrambling for cover under the assembly because it's pouring down."

The crowd was let back inside about 9.30pm.