The front that brought heavy rain to Nelson and Taranaki has now moved to South Canterbury.
MetService says a slow moving rain band is wrapped around the southern and mid parts of Canterbury, bringing about 30-40 millimetres of rain an hour - and up to 60 millimetres an hour in some parts.
Forecaster Gerard Barrow said the rain started mid-morning and got heavier this afternoon, but the heavy falls should ease by about 10pm.
He said showers would continue overnight.