Afternoon showers are being forecast for the Bay of Plenty today as the Southern Ocean storm predicted last week, moves in.

WeatherWatch.co.nz says it will also be fairly breezy with west to nor'west winds.

The weather organisation is prediction a high of 24 degrees, followed by an overnight low of 16.

'A significant and deep area of low pressure is skirting southern NZ today and brings severe weather into both islands.

'For holidaymakers the next 48 hours will be very rough in some places with gales in both islands, heavy West Coast rain and a cold change in the south.

'The low has central air pressure in the late 960hPa range. This is deep air pressure even in winter, let alone mid-summer when NZ usually has more high pressure dominating.”

Image: WeatherWatch.co.nz

RAIN & SNOW:
Heaviest on the West Coast today with over 100mm in the 24 hours from 7am up in the mountains.

'This will fall as heavy snow on the mountain tops. Slips and flooding possible. Do not cross flooding streams,” says a statement from WeatherWatch.co.nz

'Rain or showers will affect Southland, western Otago and parts of the western North Island.”

WIND:
'Severe gales spread up the Southern Alps and spread east today.

'Winds look to be strongest through Cook Strait, Wellington and Fiordland. Gusts will be up to 150km/h on the tops of the ranges and up to 120km/h at sea level.”

MARINE AND BEACHES:
Very dangerous seas are building on the West Coast with waves up to 14 metres just off from Fiordland and waves up to 10 metres moving up the coast affecting beaches like Hokitika, says WeatherWatch.co.nz

'All of western NZ should be aware of dangerous beaches and waves.

'Eastern areas may have calmer seas but remember the strong winds will be blowing out to sea – those on floatable devices could get blown away from shore incredibly quickly.”