Computer models, data and forecasters are struggling with the timing of an incoming front, expected to arrive sometime on Saturday or Sunday.

WeatherWatch.co.nz says all forecasters seem to be having trouble pin-pointing just when the rain will arrive.

“The high that is currently over New Zealand is drifting eastwards – but is now looking like it might strengthen.  This small change could have a big effect on the incoming active rain band” says head weather analyst Philip Duncan.

WeatherWatch.co.nz and other forecast providers have chopped and changed on the arrival time with the latest updates suggesting the weekend may not be that wet after all.

“What we have is a very active front moving in towards us but we also have a high holding over New Zealand which will slow and erode the front’s progress.  It’s a bit like driving at 100km/h and being able to predict your time of arrival, then turning the corner to find the traffic ahead has slowed to a crawl.  Suddenly your timing is out of whack”.

Mr Duncan says his feeling is that the West Coast will receive heavy rain on Saturday while most North Island centres will be fairly dry on Saturday.  “There may be some showers or rain which linger in isolated pockets of the North Island’s top half but most places are looking dry now for Saturday.  On Sunday the front pushes in but may have lost much of its oomph.  The heaviest rain may not arrive until Monday and Tuesday now from a new low which will be forming this weekend over Canberra”.

“The sticking point with this front is just how slow it’s moving due to the high over NZ.  Things have been moving so fast in recent weeks but for the next few days things are grinding to a halt”

WeatherWatch.co.nz will monitor the models closely and bring you the latest updates as we get them.

– Homepage image / File, www.mandenomoments.com

– WeatherWatch.co.nz