Christchurch is facing a wet and windy start to the week, with heavy rain expected, especially about Banks Peninsula, along with strong southwesterlies.

An Orange Heavy Rain Warning is in place for Banks Peninsula from 2am Monday through to 6pm Tuesday. Between 140 and 200 millimetres of rain is forecast, with heavier bursts possible Monday afternoon and evening.

Another Orange Warning covers the Kaikoura District and Canterbury north of Amberley from 8pm Sunday until 9pm Monday. Rainfall totals there are expected to reach between 110 and 150 millimetres, with peak rates of 10 to 20 millimetres per hour in hills and ranges.

Warnings are also in place for the Canterbury Plains and foothills between the Rakaia River and Amberley, where periods of heavy rain could approach warning levels and may be upgraded.

Streams and rivers may rise rapidly, with surface flooding, slips, and difficult driving conditions possible.

Residents are being urged to clear drains and gutters, avoid low lying areas, and drive cautiously as the system moves through.