Delta said electricity was cut to 350 customers in Glenorchy and 200 in parts of Fernhill and Moke Lake. Repairs were under way but could take a while.
The Queenstown Lakes District Council described the conditions as "difficult" as gale-force winds and heavy rain pounded the region.
This morning much of southern and central New Zealand remains under a heavy rain and severe gale warning.
The heaviest rain is forecast to fall on Fiordland and the Westland ranges.
Potentially damaging gales of up to 140km/h are expected across southern and eastern regions of the South Island and the bottom of the North Island.
The capital's harbour ferry service cancelled mid-morning sailings from Queens Wharf and Days Bay because of deteriorating weather conditions.
Drivers were also being warned to take care on the Rimutaka Hill Rd as winds strengthened.
