Up to 400mm of rain could hit parts of the South Island as the second of two weather systems bears down on the country. A front moved northwards over the South Island yesterday and was set to continue today, while the second system is expected tomorrow, bringing further heavy rain, strong winds and large wave conditions. Check severe weather alerts here MetService said heavy rain was expected for most of the West Coast starting this morning and continuing through until Friday or Saturday. A moisture-rich front will bring heavy rain (🟣) to the western and upper South Island tonight and Thursday. 🍃 Strong winds will affect much of the South Island as well. 🚨 Thereafter, a second round of heavy rain and wind will impact the South Island on Friday. pic.twitter.com/qPoiFeHRqn — NIWA Weather (@NiwaWeather) May 6, 2026 There was a risk of surface flooding and slips on the whole of the West Coast, MetService meteorologist Alanna Burrows said.…