The stormy weather and heavy rain that has been battering the north and west of the country is slowly closing in on Auckland.
There have been about 40 lightning strikes in the last two hours - largely offshore in Northland, MetService meteorologist Rebekah LaBar said.
Aucklanders might need to don their raincoats and umbrellas when the scatterings of rain were expected to turn heavy after 2pm.
There have been no reports of damage or severe flooding with the front so far but the rain was slow-moving, Ms LaBar said.
Auckland did not have a high chance of thunder and lightning, which was more likely to hit towards the east, but it was something to watch, she said.
"It's fairly slow-moving so there has been a bit of heavy rain in there, so that would be something especially as people get off work, to probably be aware of if there are any roads that are particularly prone to flooding. Just to be careful," she said.
"Looking at the rain radar there's been some pretty heavy rain, pretty heavy showers all the way up north and lightning strikes ... so there could be some rumbles of thunder in there as well [for Auckland]."
A heavy band of rain to the west of Auckland was currently moving in and another was coming down from near Whangarei, Ms LaBar said.
Both bands were expected to hit the city just after 2pm and could settle in before 5pm, she said.
"It'll probably be raining for a good part of the evening tonight," Ms LaBar said.
The rain was expected to clear in Auckland overnight.
MetService has issued severe weather warnings for Western Bay of Plenty, Westland and the northwest Nelson ranges, which would experience the heaviest of the rain.
Westland could expect 200mm of rain in the ranges, 150mm about the northwest Nelson (Kahurangi) ranges, and 70-100mm about western Bay of Plenty and Rotorua.
Streams and rivers could rise rapidly in these areas, slips and surface flooding could also be possible, MetService warned.
Canterbury lakes and rivers had the possibility of rising due to heavy rain before the rain moved away this afternoon.
MetService issued a watch for heavy rain on the Coromandel Peninsula and remaining areas of Bay of Plenty from this afternoon to early tomorrow morning.
A New Zealand Transport Agency spokeswoman said there had been no incidents reported to the agency so far.
Motorists should take care, increase following distances, put lights on and prepare for unexpected hazards, she said.
"There are winter driving conditions in some areas with rain and reduced visibility as well as ice in some shady areas.
"Drivers should drive to the conditions by slowing down and allowing more time for their journey," she said.