The MetService has issued a heavy rain warning for the headwaters of our lakes from 2pm this afternoon (Sunday September 1) through to 9am tomorrow morning.

Strong northwesterlies are expected today and Monday morning, with embedded fronts bringing rain, especially in the west and about the headwaters.

Expect 90 to120 millimetres of rain about the main divide, and 60 to 80 millimetres within 15 kilometres farther east.

Peak rates of 10 to 20 millimetres per hour are expected with thunderstorms possible.

Heavy rain may cause streams and rivers to rise rapidly. Surface flooding and slips are also possible and driving conditions may be hazardous.