Rain radars provide up to 90 minutes' notice of severe thunderstorms, detect pockets of heavy rain and produce high-resolution rainfall analyses for flood and catchment monitoring.
The closest radars are in Invercargill and Rakaia, Canterbury.
Without radar, forecasters have less comprehensive information about approaching rainstorms than they do in other regions.
Cr Wilson said from a farmer's perspective, let alone a civil defence one, it was frustrating not to have more certainty about rainfall predictions.
''Certain areas do not get a lot of notice.''
Given the technology was available, the risk factor and the economic benefit of having more detailed rainfall information, Dunedin and Otago should have a radar, she said.
''Our Government should fund one, as that is what it does in other areas,'' she said.
Cr Wilson had raised the issue at a recent members of Parliament forum and would be calling on community boards and other Otago councils to write in support of a radar.
''It's bizarre we do not have one in such a highly populated area.''
Otago Regional Council chairman Stephen Woodhead said he supported the push as a rain radar would be very helpful, particularly in short catchments such as the Silverstream, on the Taieri, and the Water of Leith in Dunedin.
''These can quickly flood with not much time to react.''
That meant regional council staff and the community had little time to warn or plan for major events.
''It would be extremely helpful for our work with hazards and flooding.''
A MetService spokeswoman said the only reason a radar had not been installed was the cost. MetService had a commercial contract with the Ministry of Transport and a radar for Otago was included in the weather service's 2012 and 2009 proposals to it.
''MetService ... is very supportive of the provision of severe weather warnings for Otago as a high priority service.''
A weather radar covering Dunedin city and Otago was likely to cost about $2.5 million to $3 million and take up to two years to establish.
Another option, for about a quarter of the cost, could be to move the Invercargill radar at the end of next year when it became surplus to balloon-tracking requirements, but it would be an older technology solution without dual-polarisation capability, she said.
National list MP Michael Woodhouse, of Dunedin, said what was important was not where the rain radar was located but whether the area was getting accurate information from it.
''I'm not aware that there is any problem with the information we are currently receiving.''
A Ministry of Transport spokesman said prioritisation of the rain radar's implementation was ultimately MetService's decision. It had installed five in the North Island in the past few years.
The global financial crisis meant MetService's funding was frozen for three years due to the Government's expectation of efficiencies.
In the last Budget, MetService received an extra $1.2 million, bringing its contract to $20.1 million.
''The one-off additional payment was made on the understanding that MetService is currently renegotiating its contract to provide forecasting services.''
Dunedin Labour MP Clare Curran said she was astounded the cost of a radar had been the casualty of the Government's funding freeze which had yet again left Otago ill-served.
Additional weather radars
• Taranaki 2007-08
• Gisborne2008-09
• BoP 2009-10
• West Coast 2011-12
• Far North 2012-13
Source: Ministry of Transport
