A heavy rain warning is being issued for the Eastern Bay of Plenty as an active front moves up the North Island.

The MetService is expecting rain to become heavy tonight in the eastern Bay with around 80 to 120mm of rain predicted in the next 24 to 48 hours.

Around 120 to 180mm of rain is expected to fall about the ranges with peak intensities of 15 to 20mm/h.

MetService communications meteorologist John Law says the front is set to move up the North Island today.

'This front is preceded by an extremely strong northwest flow, with very heavy rain and thunderstorms.”

In Tauranga winds speeds are expected to reach 22km/h at times today with showers predicted for the city.

Average wind speeds for tomorrow are expected to be around 10-19km/h at times.

Rainfall accumulations are predicted to reach 11.8mm about 10am – the MetService believes this is when the rain will be at its heaviest for Tauranga.

John says intense rainfalls are likely to cause rivers to rapidly rise with the risk of flash flooding in some places.

In addition, severe northwest gales are likely to continue for parts of Canterbury, Marlborough, Wellington and Wairarapa with gusts of 140 km/h.

Severe northwest gales with gusts 120 km/h are also expected to spread to Hawkes Bay and Gisborne today.