updated 16:11

Two-and-a-half thousand households are being told to prepare to be without electricity overnight after gale-force winds in Canterbury.

Orion says most customers without power are in the Banks Peninsula area.

The number still blacked out is down from 7,000 earlier today after gale-force winds caused trees and branches to fall through power lines.

Orion Chief Executive Rob Jamieson says crews are working as quickly and safely as they can to restore power. But the high winds, which are forecast to continue until tomorrow morning, are hampering their repair efforts, he says.

Orion is urging anyone in Christchurch and central Canterbury who sees a fallen power line to stay well clear and call 0800 363 9898 immediately.

Winds gusting up to 160 kilometres an hour also lifted roofs off houses and forced Air New Zealand to suspend all regional flights into and out of Christchurch.

Drivers around Christchurch are being told to be on high alert with more heavy rain and severe gales to come.

and the rest here:
http://tvnz.co.nz/national-news/hundreds-face-night-without-power-after-gales-lash-canterbury-5856780