Christchurch and Canterbury should prepare for heavy rain and possible surface flooding from this afternoon through until the middle of tomorrow. MetService last night issued severe weather warnings as the remains of Tropical Cyclone Ita drifted south to the west of the country. The deep storm system was likely to bring up to 70mm of rain to Christchurch during that period and up to 150mm about Banks Peninsula and the foothills, the service said. This will cause the foothills and plains rivers and streams to rise quickly over this period. Detailed warning messages will be posted throughout the event as required.