Weather: Thunderstorms for Hawke’s Bay, East Coast; autumn cold snap for South Island

Temperatures are expected to plunge by a whopping 10C in some parts of New Zealand as the country has its first taste of a “normal” autumn this weekend.

Balmy day-time highs of 26C will dramatically drop to just 15C and even chillier nights plunging the mercury to single digits in some southern centres.

And more rain is expected in cyclone-ravaged regions with thunderstorms expected to rumble over central and eastern regions of the North Island on Saturday and Sunday.

MetService forecaster Jessie Owen said fine weather with temperatures in the mid 20s covered much of the country today save the South Island’s West Coast.

But the warm start to the weekend would be shortlived as a southerly change swept up the country.

Rain and showers would start falling on southern and eastern areas, including Hawke’s Bay and Tairāwhiti tomorrow.

Thunderstorms were also expected to rumble across central and eastern parts of the North Island affecting communities still cleaning up from Cyclone Gabrielle.

Over the next several days, temperatures will be... in a word... changeable.

🔵 autumn 🍂 cool
🟡 summer 🏖️ warmth

🔖 https://t.co/WIN2hQ6EuY pic.twitter.com/VEQXfRhEHQ

— NIWA Weather (@NiwaWeather) March 2, 2023

While the heaviest rain was reserved for the parched South Island by the time it reached the North Island it would likely turn to showers.

“However we do have a risk of thunderstorms within those showers and they’re going to be mostly in the ranges of Hawke’s Bay and Tairāwhiti for Saturday afternoon and evening. That’s obviously not welcome news.”

On top of the wet weather, the South Island was set to see the mercury plummet to some of the coldest daytime highs felt this year.

“We are expecting a big drop in temperature, particularly for the South Island. By the time the southerly change reaches the North Island we will be seeing a little drop but only a few degrees,” said Owen.

She said it marked a return to “the normal sort of weather that we were more used to”.

Temperatures in the South Island would sit in the mid to high 20s today before dropping to the mid-teens by Sunday.

She said it shouldn’t be too bad for Auckland with the southerly petering out and bringing just a couple of showers at the most.

“There might be one or two showers across the entire region so any particular person might not see anything.”

Temperatures remained “bang on average” for this time of year, around the low-to-mid 20s.

Owen said while cooler temperatures would stick around for a few days by the middle of next week it was expected to warm up again.