New Metservice weather radar of help in Southland flooding

A tractor driver attempts to pull out a debris-covered fence near Pyramid Bridge after floods swept through the Southland town of Waikaia at the weekend. Photo / Supplied

Metservice's new weather radar station near Hindon had a significant effect on how local authorities dealt with recent flooding.

Dunedin City Council 3 Waters group manager Tom Dyer said the new facility gave council staff real-time information during the heavy rain last weekend, enabling them to monitor rainfall more accurately, anticipate where issues might arise and respond accordingly.

"The action we take during a heavy rain event is based on information from a range of organisations.

"While we have previously made preparations for flooding such as having sandbags available early as a precaution, the new rain radar was very useful in showing us exactly how much rain was falling and where.

"This level of detail helped us tailor our response accordingly."

The $3million facility is located 25km northwest of Dunedin, 750m above sea level, and provides excellent coverage of Dunedin city, the Taieri and Clutha River catchments, and eastern Otago from the Catlins to Waitaki.

Otago Regional Council operations general manager Gavin Palmer said the new weather radar joined a range of data inputs for more accurately predicting and understanding weather hazards facing coastal Otago and particularly South Dunedin, which was prone to flooding.

"The rain radar allows us to see at a glance where it is or isn't raining and at what sort of intensity, in real time.

"This is really beneficial to our situational awareness during a flood event, in which our 24/7 duty flood officers are taking in detailed information from several sources and needing to rapidly analyse it to draw conclusions during developing events.

"Over time, the data set from the radar will also improve our accuracy in modelling how events will develop in terms of impacts on river levels," he said.

MetService switched on New Zealand's newest weather radar in early December.

MetService acting chief executive Keith Hilligan said it used the latest dual polarisation technology, which could identify different types of precipitation, be it rain, hail or snow.

Aside from its forecasting value to MetService meteorologists, real-time radar data was of great importance to hydrologists, emergency management staff and the coastal Otago community, to plan, prepare and make decisions based on the likely impact of weather, he said.

"The radar further strengthens our national radar network, while providing additional resilience to Otago communities, especially in severe weather events."