Heavy rain and severe easterly gales are possible over the upper North Island Sunday.

The MetService has issued a severe weather watch for most of the North Island, including the Bay of Plenty.

"A deep low is forecast to approach New Zealand from the north on Sunday, directing a strong and moist northeast flow over the upper North Island.

"There is uncertainty as to the exact track and depth of the low as it approaches, and possibly passes over, New Zealand on Sunday."

The watch covers the possibility of a deep low moving southeastwards over the upper North Island during Sunday, delivering severe gale easterlies to exposed parts of Northland, Auckland including Great Barrier Island, Coromandel Peninsula, Waikato and Bay of Plenty west of Whakatane.

"In addition, rainfall accumulations would likely reach warning amounts in the same regions, excluding southern Auckland and Waikato on Sunday.

"King tides are also forecast for Sunday, and in combination with lowering air pressures expected with such a deep low and large northeast waves, coastal inundation could affect coastal areas in these regions exposed to the north and east."

HEAVY RAIN WATCH

Area: Northland, northern Auckland including Great Barrier Island, Coromandel Peninsula and Bay of Plenty west of Whakatane

Valid: 12 hours from 6am to 6pm Sunday

Forecast: Rain accumulations may reach short duration warning amounts during this time, for example 70mm in 12 hours or less.

STRONG WIND WATCH

Area: Northland, Auckland including Great Barrier Island, Coromandel Peninsula, Waikato, Waitomo and Bay Of Plenty west of Whakatane

Valid: 15 hours from 6am to 9pm Sunday

Forecast: Easterlies may rise to severe gale in exposed places during this time.

Sunday's weather system may affect low-lying coastal areas

MetService has issued a severe weather outlook for the weekend.

Waikato Regional Council (WRC) is monitoring the weather system which has the potential to affect some of the region's low-lying coastal areas on Sunday.

'Better information is expected overnight and an update will be issued tomorrow,” says WRC hazards team leader Rick Liefting.

'At this early stage, the weather system is due to arrive in the region on Sunday and is expected to produce north-easterly gales. Combined with the king tide cycle peaking from Saturday to Monday, there is the possibility of localised inundation of low-lying coastal areas, particularly on the Kaiaua Coast and Pūkorokoro-Miranda, but potentially on Coromandel's east coast too,” says Mr Liefting.

On Tuesday, a new ridge of high pressure should bring more settled weather.

'The extent and impact is currently uncertain, however, for the Kaiaua Coast and Pūkorokoro-Miranda area the impacts are likely to be less than those experienced in January.

'The east coast of the Coromandel will likely experience large waves associated with the north-easterly winds, which may cause localised inundation and/or erosion.

'The weather system on Sunday is also predicted to include heavy rain, primarily along the Coromandel Peninsula. So there may also be river flooding impacts, especially over high tides.”

Mr Liefting said MetService forecasts were being monitored and they would have a better understanding of the potential effects on Saturday.

Hauraki District Council staff will be monitoring potentially affected areas over peak tide times.

In the meantime, people in coastal areas such as the Kaiaua Coast and Pūkorokoro-Miranda and, to a lesser extent, Whiritoa, should keep an eye on the MetService for the latest weather forecasts and be prepared with supplies just in case they are cut off.

Other things to think about and plan for, in case they are needed, could include lifting things off the floor, covering gully traps and septic tank mushrooms with plywood, disconnecting and raising water pumps, putting plywood in front of exposed windows, moving vehicles to higher ground, and filling sandbags.

Sandbags are available at the following locations:

Kaiaua Fire Station. Please contact Chief Fire Officer Owen Macdonald to collect

Whiritoa Fire Station. Please contact Chief Fire Officer Mike Jacob to collect