Heavy and sustained rain has filled Fiordland lakes and necessitating Te Anau's hydro control gates to be further opened.

The Met Service has issued an orange alert level - heavy rain warning for Fiordland, from 8am - 9pm today (1 Jun).

Te Anau's historic town wharf after heavy rains fall in Fiordland. Photo: Southland App

The Upper Waiau River is currently flowing at 666.89 cubic metres per second (cumecs) at Rainbow Reach, after Te Anau's hydro control gates were further opened.

This is the rivers highest flow at this location since August 2022, when it peaked at around 640 cumecs.

The Upper Waiau River is in full flood after heavy rain forces Lake Te Anau control gates to be opened further. Photo: Southland App

The Met Service forecasts heavy rain with possible thunderstorms today, however this should ease to showers tonight.

Snow is expected to 1800 metres, lowering to 700 metres this evening.

Showers are expected to continue throughout tomorrow and into the long (Kings Birthday) weekend.

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