The ACT State Emergency Service received 77 calls for help from tonight's storm.
A spokesman said crews responded to minor flooding from leaking roofs, mainly in the Tuggeranong Valley, and to trees and branches across roads.
The Bureau of Meteorology has lifted a severe thunderstorm warning for Canberra and Queanbeyan.
"Severe thunderstorms are no longer affecting Canberra and Queanbeyan. The immediate threat of severe thunderstorms has passed, but the situation will continue to be monitored and further warnings will be issued if necessary," it said in a statement at 9.27pm.
Earlier, a severe thunderstorm warning issued at 5.11pm carried the information that a tornado had been reported in the Bredbo area south of Canberra with hailstones at least 2cm in size.
The bureau said there was an 80 per cent chance of rain in Canberra tomorrow, including the chance of isolated morning showers and "scattered showers and thunderstorms from midday". It also forecast possible showers each day until the end of next week.
Weatherzone meteorologist Alex Zadnik said rainfall had bucketed down across Cooma during the day, with two separate severe storm cells crossing the town.
A total of 45mm of rain was recorded between 9am and 4pm, with 11mm of this falling in the space of 10 minutes.
He said the severe thunderstorm activity seen so far today had been triggered by a low pressure trough over southern NSW, combined with high levels of atmospheric moisture.
This low pressure trough would remain slow-moving tomorrow, so there would again be the risk of thunderstorms across much of NSW, but particularly on and west of the Dividing Range.
The trough would weaken and drift westwards on Sunday, reducing the risk of severe storm activity over NSW on this day.
The State Emergency Service is advising people to move cars under cover and secure loose items.
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