Weather: Warning as severe storm, heavy rain loom for Auckland, regions

Local Civil Defence groups are warning residents to be prepared for localised floods and heavy downpours starting from Thursday night.

A number of heavy rain watches and warnings are in place around the country, as a complex trough crosses much of northern and central New Zealand on Friday.

Affected residents are being advised to clear drains and gutters, avoid low-lying areas and drive cautiously.

Local Civil Defence and emergency mangement groups for Northland, Auckland, Waikato, and Bay of Plenty are reiterating MetService’s information on the watches and warnings.

What’s expected in each region?

A heavy rain watch and severe thunderstorm watch are in place from Thursday night until Friday for most of the regions at the top of the North Island and some on the west of the South Island.

• Between 3pm Thursday and 11am Friday, localised downpours of 25-40mm/h may affect parts of Northland at times. The thunderstorm and downpour risk initially starts in the Far North this afternoon, then spreads southwards to other parts of Northland this evening.
• Localised downpours between 25-40mm/hr are possible with severe thunderstorms, this might cause some surface flooding in some areas if these totals are reached. The heavy rain watch is in place from 8pm Thursday until 2pm Friday. The severe storm watch is n place from about 10pm tonight and 5am Friday.
• An orange heavy rain warning is in place for Bay of Plenty and Rotorua from 3am until 8pm. Expect 80 to 110 mm of rain to accumulate. Peak rates of 15 to 25 mm/h, but rates of 25 to 35 mm/h possible in localised downpours and thunderstorms.
• A heavy rain watch from 6am to 9pm Friday is in place for Taupo, with periods of heavy rain expected. Rainfall may approach warning criteria. Thunderstorms are also possible.
• Mt Taranaki can expect the same as Taupo – except their watch is in place from 11pm Thursday to 7pm Friday.
• An orange heavy rain warning is in place for Tasman northwest of Motueka from 6pm Thursday to 6pm Friday. Expect 120 to 150 mm of rain to accumulate. Peak rates of 15 to 25 mm/h.
• A heavy rain watch is in place for Fiordland north of Doubtful Sound and the ranges of the Westland District from Thursday morning until Friday 4am. Periods of heavy rain are expected, and amounts may approach warning criteria

Warning to Aucklanders

Auckland Council emergency management general manager Adam Maggs said residents should take precautionary measures before the rain was expected to set in from about 8pm.

“Just check the drains around the property, if [residents have] got things that are loose and laying around, tuck them away, just do some of those checks that you’d do if you know some weather’s coming in,” he said.

“We’re not expecting huge volumes of rain, but we are expecting lots of showers and messy weather coming from the north and the east.”

The northern and eastern parts of the region could see more rain than other areas, Maggs said.

Heads up Auckland ⛈

Our expert forecasters have decided to issue a Severe Thunderstorm Watch for potential downpours with the rain tonight.

Some areas could see larger accumulations of rain than others & impacts are possible with the high intensity rainfall.@AklCouncil… pic.twitter.com/RG6FjbDVhx

— MetService (@MetService) June 12, 2024

The rain would likely exacerbate already damp conditions, he said.

“Soils are saturated, so we’re going to see run-off off the land, and there will be localised flooding likely,” he said.

“Water’s got nowhere to go except basically run-off, so we’re likely to see, even with reasonable numbers, some localised flooding on some of our roads, some of the areas that would typically see surface flooding, might see that surface flooding until it’s got time to drain away.

“We’re not talking huge volumes of rainfall, just the fact that, at this time of year, we’re already pretty wet anyway and we’ve just got more rain coming.”

Residents should report any blocked drains or fallen trees to the council.

“If people see trees down, report a problem on the Auckland Council online website, it’s important, and any blocked drains, feel free to call Auckland Council on 09 301 0101, and we’ll get that resolved,” Maggs said.

He warned rain could still be pouring on Friday morning, and advised motorists to take care on the roads and drive to the conditions.