Flooding has forced the closure of State Highway 1 to Blenheim and Picton at Seddon in Marlborough as wet weather hits parts of the South Island.
Waka Kotahi NZTA says the highway is likely to be closed all day at Seddon.
It is possible that more highways may be closed due to flooding as the day progresses, Waka Kotahi's Tresca Forrester said.
“Please slow down and drive to the conditions if there is surface flooding to avoid making waves. People should expect roads that are open to be slower than usual with damage from last week’s storm creating some slower patches in many places across our network.”
Waka Kotahi advises that people who need to get to or from Picton or Blenheim today should take the Lewis Pass route north of Christchurch, SH7, Waipara turnoff from SH1, then SH65, the Shenandoah Highway via Maruia, SH6 to Murchison then SH63 via St Arnaud to Blenheim.
There are heavy rain warnings in place for Tasman, Canterbury (north of Raikaia River) and Otago.
In Christchurch there's been surface flooding in some places.
It rained through the night and the City Council earlier warned Christchurch and Banks Peninsula residents to prepare for more flooding and slips this week as another band of rain arrives.
Environment Canterbury has warned that the Ashburton River catchment could overflow.
"High flows expected in the Ashburton River catchment [on Tuesday] and into Wednesday,"
"Overflows possible in vulnerable areas. Please monitor your own situation and take action to prepare."
Some South Island mountain passes were closed earlier on Tuesday due to snow. All have now reopened.
Severe weather overnight has left parts of the Coromandel Peninsula inaccessible on Tuesday.
State Highway 25A is closed between Thames to Huakai due to slips, and to the east, State Highway 25 is closed from Waihi to Whiritoa.
Multiple main roads further up the peninsula are also closed by flooding or slips, cutting off access to Whitianga and Coromandel Town.
Around 300 properties in the area are without power.
The Thames-Coromandel District Council warns anyone who needs to travel in the region to expect delays.
Councillor and emergency management committee chair Sally Christie told Breakfast the key message was to stay home.
“There are communities cut off, but really, we are specialists here at looking after each other, we have community response plans, so look after your neighbours,” she said.
“The other really, clear message I’m wanting to tell people is not to take risks... don’t try and walk, swim or drive your way out of trouble, stay safe.”
Christie added that “by the end of the day we’ll have some roads open” but people should be prepared for more bad weather to come.
In the Bay of Plenty, State Highway 33 is blocked by a slip between Rotorua and Paengaroa. Police warn the road is likely to be closed all day.
A heavy rain warning is in place in Bay of Plenty.
In Northland some farms have been swamp in floodwater which will take some time to recede. The flooding comes during calving season.