“What we are more likely to see is Oma moving off towards north Queensland but still playing a role in bringing moisture down to New Zealand but certainly not in the quantities it would have if it had taken a track over NZ,” Weather Watch forecaster Philip Duncan says.
It has taken some time for the European and United States weather models to start coinciding in terms of where they expect precipitation to fall and that is looking patchy at best.
“For example, parts of Waikato now have the chance of receiving only a small amount of rain.
“We see heavy rain just north of NZ but it won’t be sliding south.”
Rainfall amounts might be as low as 10mm in Waikato, possibly as high as 150mm in a narrow band of precipitation through the lower North Island and possibly the eastern side of the South Island.
MetService rainfall modelling has the Far North experiencing moderate rain intensity by Friday night and significantly lighter through Waikato and lower North Island.
By Saturday morning much of the North Island is expected to have experienced lighter rain that might extend until later Sunday.
Weather Watch modelling has the biggest winners from the system being Wairarapa, expected to receive 50-60mm in total to next Tuesday, with Waikato about 20mm and the upper South Island about 15mm.
As the high-pressure system positions itself forecasters expect strong southerlies and cooler temperatures.
Duncan said the system will intensify into another significant high-pressure system, likely to dominate the weather pattern through to the end of the month.
