Heavy rain is sweeping east across New Zealand’s North Island, and now orange warnings are in place for parts of the Bay of Plenty and Gisborne Tairāwhiti. A slow-moving front is behind all this, bringing rain that could cause real problems.
MetService says the areas under warning could see up to 120 mm (almost 5 inches) of rain, and at times it could pour down at 10 to 20 mm an hour.
Earlier, this same weather system hit Northland and Auckland with heavy rain before it worked its way east. By August 13, the main concern is shifting to the eastern North Island, where steady rain combined with the region’s mountains can make streams and rivers rise quickly.
The New Zealand Transport Agency Waka Kotahi is warning drivers to take care—slips, fallen trees, and sudden road closures are all possibilities as this rain sticks around.
🌧️Severe Weather Update – Heavy Rain🌧️
— MetService NZ (@MetService) August 12, 2026
🟠A Heavy Rain Warning is now in force for the Bay of Plenty area west of Kawerau
🟠A Heavy Rain Warning has been issued for Gisborne north of Tolaga Bay.
🟡 A Heavy Rain Watch has also been issued for the Bay of Plenty area about and east… pic.twitter.com/NVzKUcAxhT
Right now, the Bay of Plenty west of Kawerau is under an orange heavy rain warning that lasts until 3pm Thursday. Over in Gisborne Tairāwhiti, north of Tolaga Bay, the same warning is in place until 8pm Friday, so the risk of rain hangs around longer in that area.
There’s also a heavy rain watch for the Bay of Plenty around Kawerau and eastward until 9am Friday.
According to MetService, this rainmaker is crawling east across the Bay of Plenty, Rotorua, and Gisborne Tairāwhiti during Thursday and Friday.
Although the worst of the rain has passed in Northland and Auckland, showers could still pop up just about anywhere as the bigger weather system keeps moving through.
Why does the Bay of Plenty get so much rain?
The North Island’s hills and mountains really crank up the rain in situations like this. Moist air coming in from the ocean slams into the terrain, forcing the air upward.
As the air rises, the pressure drops, the air cools, and eventually, it can’t hold all its moisture. That’s when clouds form and the rain starts.
This is called orographic enhancement, and it can push up rainfall totals on hills and mountains compared to nearby lower spots.
That’s why one area might get hit with heavy rain while a spot just a short drive away gets way less. All that extra water then drains into the valleys, streams, and rivers below.
The speed of this front is another key factor. When a front moves fast, the heavy rain usually doesn’t stick around as long. But a slow front like this lets damp, rainy air linger over the same spots much longer.
With up to 120 mm (4.72 in) expected and hourly peaks of 20 mm (0.79 in), the ground can get soaked quickly. Past a certain point, the soil can’t absorb any more, and extra rain turns into runoff. MetService says this means streams and rivers can surge, with surface flooding and slips (landslides) possible.
People are being told to clear gutters and drains, and stay away from low-lying areas where water might build up. Roads could get tricky, and closures may come fast
NZTA is telling everyone travelling in the next day or two to drive with headlights on, give themselves extra space from other cars, and be ready for surprises. Road closures could happen suddenly if landslides, fallen trees, or damaged roads crop up.
Road crews are keeping an eye on main highways—especially places like the Waioweka Gorge, where steep hillsides make it even more likely to be blocked or washed out by the rain.
And just because the rain starts to ease doesn’t mean the danger is past. Wet slopes stay unstable, and rivers can keep rising as all that runoff moves downstream. So even if the skies start to clear, the risk can stick around.
This latest bout of wet weather follows a pretty unsettled winter for New Zealand, with heavy rain bouncing from Northland and Auckland over to the east.
As the front keeps moving east, people are really watching Gisborne Tairāwhiti now, since the orange warning there doesn’t expire until Friday night.
