Heavy rain across the Upper Clutha is causing significant surface flooding, and wider afield a state of emergency has been declared in Gore, and the Haast Pass is closed overnight due to a slip.

In the past five hours more than 30 millimetres of rain has fallen in Wānaka and the MetService says the rain will continue until late tonight (Thursday September 21).

Many parts of the Upper Clutha are experiencing significant surface flooding making driving hazardous, and Mt Aspiring Road is closed due to rising fords.

Surface flooding is also affecting travel through the Kawarau Gorge.

Earlier today SH6 to Cromwell was closed south of Luggate because of fallen trees. Update 7.20pm: SH6 is closed again due to flooding (check Roads).

The entire Upper Clutha was without power during the afternoon due to faults which Aurora progressively repaired. As of 6pm the Luggate and Queensberry area were still without power which Aurora says it hopes to have restored by 9.30pm.

A snowfall warning is in place for the Crown Range Road and the Lindis Pass with snow expected to affect travel from around dawn Friday (September 22) morning through to midday. 

The Lindis Pass can expect 2-3cm of snow and the Crown Range 1cm. 

MetService says while the snowfall is not expected to be as heavy as previously forecast a watch remains in place for snow above 600 metres.

Drivers are advised to carry chains if travelling either route in the morning.

Further rain is forecast across Friday but falls are not expected to be as heavy as today. The rains will clear Friday evening. 

PHOTO: Wānaka App