Winds strong enough to down power lines, uproot trees and make driving "hazardous" are expected to batter Otago.

The MetService has issued a severe weather warning for all of Otago from the early hours of tomorrow.

A front was expected to move over the South Island bringing northwest gales of up to 140kmh to Otago, especially in exposed places.

MetService communications meteorologist Lisa Murray said the wind could do damage to unsecured structures.

"The whole of Otago is under a wind warning. We're going to get gusts of at least 120kmh.

"We could very well get gusts of 140kmh in the early hours. Winds of this strength have the potential to bring down trees and power lines, damage unsecured structures and make driving hazardous, particularly for high-sided vehicles and motorcycles," Ms Murray said.

Behind the front, a cool southwest change would follow, which would bring "severe gales" to parts of coastal Southland and Otago.

"During Thursday, a southerly change is going to come through.

"Winds should turn southwest.

"About the coast from the Otago Peninsula southwards, severe southwest gales gusting 120kmh are forecast for a time tomorrow evening."

Brief showers were also forecast for the region with some inland areas getting heavy showers, Ms Murray said.

"We advise people to be aware of the weather," she said.

• State Highway 94 will close from Hollyford from 8pm tonight due to expected heavy rain. The rain is expected to affect a rock fall site near the Lower Hollyford so the road will close for safety reasons.

rhys.chamberlain@odt.co.nz