Transit keeping close eye on South Island snow

Chains are essential on some mountain passes in the South Island, but all roads are open this morning.

Otago area engineer for Transit John Jarvis said snow has fallen inland and contractors are out assessing the situation.

"We're warning people to check road reports on the website. It could change quite quickly," Mr Jarvis said.

Chains are essential on the Haast and Lindis Pass and more snow is expected later today.

"Whether it's as bad as the last event, we don't know yet," Mr Jarvis said.