The first seven minutes of a thunderstorm that hit the ACT on Saturday delivered 3.4 millimetres of rain and hail, knocking out power in parts of Canberra and Queanbeyan.
Bureau of Meteorology data shows 3.4 millimetres of rain fell at Canberra Airport between 12.04pm and 12.11pm. A further 0.8 millimetres of rain was recorded before 12.45pm.
The 4.2 millimetres of rain, recorded in the space of 41 minutes, surpassed the daily rainfall totals recorded at Canberra Airport for all but 16 days of the year.
Evoenergy reported unplanned power outages in Acton, Ainslie, Barton, Campbell, Parkes and Reid, but power was restored shortly after 2pm. The outages affected venues including the National Museum of Australia and Questacon.
Essential Energy acting regional manager Mathew Rogers said the company had restored power to about 6300 customers across south eastern regional and rural NSW by Sunday morning, and the last few would be reconnected soon.
“Around 1500 customers in Queanbeyan were affected by a power outage, with other outages affecting customers in the Cowra, Young, Boorowa, Yass, Crookwell, Goulburn, Braidwood and Cooma areas,” he said.
“Supply was progressively restored to most customers by 11.30pm, however, a small number of customers around Queanbeyan, Crookwell, Braidwood, Yass and Young remained without supply overnight.
“We anticipate that power will be restored to all customers today [Sunday].”
A National Museum of Australia spokeswoman said power had been restored and the museum had reopened to the public following safety checks.
'We apologise for the inconvenience. Visitors who came to see the 'Rome: City and Empire' exhibition from the British Museum will be offered free tickets or refunds." the spokeswoman said.
Across the border, the storm knocked out power for 1448 Essential Energy customers in the Queanbeyan area at 12.10pm. A spokesman said power was restored shortly before 2.30pm.
The Bureau of Meteorology issued a severe thunderstorm warning ahead of the storm, warning of the potential for large hailstones, damaging winds and heavy rainfall.
The warning was cancelled for the ACT and surrounding areas at 1.15pm but heavy rain continued throughout the afternoon.
The amount of rain recorded at Canberra Airport for the day had reached 9.4 millimetres by 5pm.
Shortly after 1pm on Saturday, bureau meteorologist Kat Kovacevic said the worst of the conditions had passed after a trough moved through from the west.
Ms Kovacevic earlier said the trough, combined with warm temperatures and humid conditions, acted as "a thunderstorm trigger".
An Emergency Services Agency spokeswoman said firefighters and the State Emergency Service were called to a house in Ngunnawal about 4.25pm on Saturday.
Blocked gutters had caused water to build up and start flowing through the walls of the house, she said.