As the wet weather moves back into the northern and western parts of the country, a number of heavy rain watches have been issued for various regions across the country.

A heavy rain warning has been issued for Northland from 6 am Tuesday to 9 pm Tuesday.

According to the MetService website, rainfall amounts "may exceed" its warning criteria, and there is a good chance it will be upgraded to a warning.

Heavy rain and squally thunderstorms are possible in Auckland.

Expect 50 to 70 mm of rain, with higher amounts possible in isolated areas.

Thunderstorms and downpours of 40 mm per hour or more are possible in isolated areas, with intensities ranging from 10 to 15 mm per hour.

Meteorologists warn that the heavy rain could cause streams and rivers to rise quickly.

Surface flooding and slips are also possible, as are hazardous driving conditions.