The MetService said last night there would heavy rain in affected areas - reaching 60mm in some areas in a span of nine hours.
WeatherWatch said a small but very "potent burst'' of rain was heading our way.
"Best estimates is that this torrential rain will brush Northland, potentially Coromandel Peninsula, but could be most intense through Bay of Plenty and into the Gisborne and northern Hawke's Bay ranges,'' Duncan said.
"This rain may cause flooding and slips in these areas and affect state highways.''
It is also thought that winds in the system will change a lot during its time here with potential for wind tunnels to form.
"Wind damage may be in certain areas rather than widespread, with various wind tunnels being one factor and the other factor being the damaging winds right at the centre of [a new] low.
"But these winds will only cause damage near the centre. So if the centre remains out at sea, so too will the worst of the winds.''
The MetService said the latest models predicted Hola moving swiftly and skirting the north east of the North Island today; bringing severe weather to eastern parts of the upper North Island.
There could be rain accumulations of up to 150mm and wind gusts of 130km/h for eastern parts, from Northland to northern Hawke's Bay.
There are severe weather warnings and watches in place.
Heavy rain warnings have been issued for Northland, Great Barrier Island, Coromandel Peninsula and Gisborne.
Strong wind warnings are in place for Northland, Great Barrier Island, Coromandel Peninsula, Auckland, Bay of Plenty, Rotorua and Gisborne.
The MetService is warning people in these areas to monitor weather updates, as heavy rain could cause streams and rivers to rise rapidly.
Surface flooding and slips are also possible, the MetService warns, so motorists are encouraged to be aware of potentially hazardous conditions.
Meanwhile, Vector said it had crews on standby in case the cyclone did any damage to the electricity network.
Chief network officer Andrew Botha said teams were ready to head out as soon as it was safe to do so should any lines came down because of stormy conditions.
Botha urged people to tie down things like trampolines and outside furniture which may be thrown around in the storm.
"And please, always treat downed lines as live and stay well clear.''
HEAVY RAIN WATCH:
Auckland, Waikato, Bay of Plenty west of Te Puke and the eastern ranges,
Hawke's Bay north of Hastings:
Rain is expected to develop early tomorrow morning , with some heavy falls, then easing in the evening.
Rainfall accumulations may reach short duration warning amounts (60mm in nine hours)
STRONG WIND WATCH:
Taupo, Hawke's Bay from Hastings northwards: Gale south-easterlies developing tomorrow afternoon, may rise to severe gale strength in exposed places, before turning southerly in the evening and winds gradually easing.
Source: MetService