Most of the North Island will remain dry tonight and tomorrow as settled weather remains in place thanks to a big high pressure ridge to the east of New Zealand.

On the South Island, it’s a very different story.

Eastern Otago could end up being pretty dry over the next 36 hours.  But the rest of the Mainland is looking pretty rainy.

Especially Westland where heavy rain is expected.  Government forecaster MetService has several heavy rain warnings in effect.

• Ranges south of Fox Glacier- Heavy rain is expected tonight and during the overnight with some rainfall rates approaching 15 to 25mm/hr.  Rainfall totals are expected to reach 120 to 140mm.  50 to 70mm is possible along the coast.

• Ranges between Fox Glacier and Otira/Arthurs Pass- Heavy rain is expected tonight through early tomorrow afternoon.  Rainfall rates may approach 15 to 20mm/hr.  Totals of 100 to 140mm are expected with 50 to 70mm near the coast.

• North of Otira/Arthurs Pass- Heavy rain is expected overnight tonight through tomorrow afternoon.  Totals of 80 to 120mm are expected.  Rainfall rates of 10 to 15mm/hr are possible with the heaviest rain occurring late tomorrow morning.

Heavy rain will continue to shift north late on Sunday and will likely affect Nelson.  Heavy rain will remain a threat for Nelson into Monday as well.  No warning is in effect at this time, but it is something that will have to be watched.

Some brief heavy rain may also affect parts of the North Island on Monday with Taranaki and Northland having the highest risk.

Homepage image/ Rachel Kuljish

By WeatherWatch.co.nz Analyst Howard Joseph