A significant rain event is impacting the West Coast from today to the end of Sunday with rainfall totals of 250mm to 300 at the coast and potentially half a metre of rain (500mm) in the mountains.

The bulk of the heaviest rain will be in the middle section of the West Coast and further southwards – or from about Hokitika southwards. Rainfall totals dramatically drop off the further north you go, which is better news for places like Greymouth and Westport.

Franz Josef is one area that is most exposed with WeatherWatch.co.nz forecasting at least 270mm there over the next 3 days, but totals further inland may exceed 500mm, which is a huge amount of rain falling in fairly short period of time. This may well lead to slips, flooding and some road closures.

It’s worth noting that the 400 to 500mm possible totals will be quite isolated and may not show up on all rain forecast maps. For the most part rainfall totals look to be 200 to 300mm over the coming three days in the main risk area.

• You can now find all MetService weather warnings LIVE on the WeatherWatch website: www.weatherwatch.co.nz/maps-radars/warnings/metservice. MetService is also warning that “500mm+” is possible.

• Track the Rain LIVE with our new Real Time/Live Rain Radar courtesy of MetService: www.weatherwatch.co.nz/maps-radars/radar/rain-radar-realtime
• Hyper-local Rainfall graphs and totals can be found at: www.RuralWeather.co.nz
• Rain Accumulation Maps: www.weatherwatch.co.nz/maps-radars/rain/accumulative-rainfall