Hi there. The main reason is because the southern regions of both islands are fairly complicated. Southland not only has Stewart Island blocking rain but also the Fiordland ranges are enormous mountains that come out of no where and do a great job at blocking rain – and making for much higher rainfall totals in the west. The southern North Island is even more complicated as the South Island/Southern Alps all block south to south west rain events for some – which is why Taranaki has had good rain but more to the east (in the shadow of the South Island) lies Manawatu – the driest region now. No El Nino or La Nina – we have a ‘normal’ pattern in our part of the world but the highs are very big for this time of the year. Tropics are quiet now but may still pick up in late April, or even May this year. The big amount of high pressure in the NZ area so far this year has blocked cyclones from reaching us – we’ve had 3 close calls though (last year 3 hit us – this year 3 tried to, but couldn’t due to high pressure protecting NZ).

Cheers

Phil D