In the headwaters of the Canterbury lakes and rivers, about and south of Arthur’s Pass, rain is expected from 5pm on Sunday and may last 12 hours with up to 170mm falling.
Up to 100mm of rain is expected over 12 hours from 2pm Sunday around the main divide – in and about the headwaters of the Otago lakes and rivers.
A heavy rain watch has been put in place for the ranges of Grey and Buller with inclement weather expected from 6pm Sunday for about 12 hours.
“Northwest winds may approach severe gale in exposed places,” MetService said.
In all regions, the safety advice was the same.
“Thunderstorms are possible… Streams and rivers may rise rapidly. Surface flooding, slips, and difficult driving conditions possible,” said the latest MetService weather information.
“Clear your drains and gutters to prepare for heavy rain. Avoid low-lying areas and drive cautiously.”