Heavy snowfall has provided fun for Canterbury families but has caused trouble for motorists, prompting police to urge drivers to delay any unnecessary travel due to poor conditions across the region.

SH73 is closed from Springfield to Castle Hill, with numerous vehicles stuck at Castle Hill and the Lake Lyndon area.

A police spokesman said other alpine areas are also experiencing heavy snowfall.

Elsewhere across the region there have been reports of surface flooding and snow.

Anyone who has to travel is urged to ensure they are doing so with the appropriate equipment, such as snow chains.

Meanwhile, roads in Christchurch have experienced flooding.