A deep low lies west of the North Island, and is expected to move east across the lower North Island today, with west to northwest gales on its northern flank says MetService.

Warnings and Watches for Heavy Rain and Severe Gales are in force.

People are advised to keep up to date with the latest forecasts, as further Watches or Warnings may be added.

A Heavy Rain Watch has been issued for these regions:

Area: Tongariro National Park
Valid: 14 hours from 1:00pm Sat 20 May to 3:00am Sun 21 May
Forecast: Periods of heavy rain. Rainfall amounts may approach warning criteria.

Area: Mount Taranaki
Valid: 25 hours from 8:00pm Fri 19 May to 9:00pm Sat 20 May
Forecast: Periods of heavy rain. Thunderstorms possible. Rainfall amounts may approach warning criteria.

A Strong Wind Watch has been issued for these regions:

Area: Northland
Valid: 18 hours from 9:00pm Fri 19 May to 3:00pm Sat 20 May
Forecast: Northwest winds may approach severe gale at times.

Area: Auckland including Great Barrier Island
Valid: 12 hours from 9:00am Sat 20 May to 9:00pm Sat 20 May
Forecast: Westerly winds may approach severe gale at times.

Area: Coromandel Peninsula
Valid: 12 hours from 1:00pm Sat 20 May to 1:00am Sun 21 May
Forecast: Northeast winds have eased. However, westerly winds may approach severe gale at times.

Area: Waikato, Waitomo and Bay of Plenty west of Te Puke
Valid: 13 hours from 12:00pm Sat 20 May to 1:00am Sun 21 May
Forecast: West to northwest winds may approach severe gale at times.

Area: Taumarunui, Taupo, Taihape, Whanganui, Manawatu and Hawkes Bay
Valid: 15 hours from 6:00pm Sat 20 May to 9:00am Sun 21 May
Forecast: West to northwest winds may approach severe gale at times.

Area: Gisborne
Valid: 20 hours from 3:00pm Sat 20 May to 11:00am Sun 21 May
Forecast: Northeast winds have eased. However, west to northwest winds may approach severe gale in exposed places.

Area: Taranaki
Valid: 25 hours from 8:00pm Fri 19 May to 9:00pm Sat 20 May
Forecast: North to northeast winds may approach severe gale at times. Winds should turn northwest Saturday morning, and then westerly Saturday afternoon.

A Heavy Rain Warning has been issued for this region:

Area: Tasman west of Motueka
Valid: 19 hours from 8:00pm Fri 19 May to 3:00pm Sat 20 May
Forecast: Expect a further 90 to 120 mm of rain to accumulate about the ranges (on top of what has already fallen) with lesser amounts elsewhere. Thunderstorms possible. Peak rates of 10 to 20 mm/h.

Heavy rain may cause streams and rivers to rise rapidly. Surface flooding and slips are also possible and driving conditions may be hazardous.