Heavy rain overnight has caused severe surface flooding in the Gisborne suburb of Mangapapa, forcing some families to leave their homes.

Tairāwhiti Civil Defence says 15 households were evacuated overnight.

It says heavy rain caused drains to flood and creeks to rise to about 2m, causing severe surface flooding across the suburb.

MetService has issued an orange heavy rain warning for the city and police have been going door-to-door checking on people.

Fire and Emergency has closed roads in and around the areas from Lytton High School to Winter Street.

Gisborne mayor Rehette Stoltz says severe downpours started at 3am, and three hours later it was still "pouring".

"The rain woke everyone up in Gisborne," Stoltz told Morning Report.

"It's rain I have not heard in my 22 years in Gisborne."

Intense rain of up to 40mm is expected up to about 8am from the South of Waipiro Bay to Gisborne City, says Tairāwhiti Civil Defence.

Stoltz says city creeks are overflowing and flooding people's homes.

More rain fell overnight in Hawke's Bay with reports of flooding in some areas.

Napier mayor Kirsten Wise says there are reports of flooding in the city and people should stay off the roads where possible.

-RNZ.