Cyclone Tam’s final punch sparks thunderstorm watch for Hawke’s Bay

MetService has issued a severe thunderstorm warning for inland Hawke's Bay. Photo / Glenn Taylor

The final flurry of fists from Cyclone Tam will hit the central North Island Monday afternoon, prompting MetService to issue a severe thunderstorm watch for inland Hawke’s Bay and neighbouring regions.

A slow-moving area of low pressure is affecting the North Island, while a warm, moist and low-level convergence are likely to generate showers and possible downpours, with moderate risk of severe thunderstorms from Monday afternoon into the evening.

MetService meteorologist Alec Holden said that while Cyclone Tam is spinning off the western edge of the Cook Strait, it’s casting long lines of unstable showers across the North Island, with thunderstorms hitting an already sodden Coromandel on Monday morning.

The severe thunderstorm watch is in place from 1pm to 9pm Monday for inland Hawke’s Bay, southwestern Gisborne, Rotorua, Bay of Plenty, and Taihape.

“[For Hawke’s Bay] it is up in the ranges and inland, so all the areas down on the coast are unlikely to see anything serious but it is those out to the west and up in the elevated terrain where we are most concerned,” Holden said.

“We are looking at rain rates of between 25 to 40mm an hour, which is proper torrential downpours, and hail along with the lightning.

“So, it will be quite the unpleasant experience if you find yourself underneath one of those. If you do, make sure not to shelter under tall objects like large trees.”

Civil Defence NZ recommends avoiding standing near tall structures or elevated areas such as towers, tall trees, or hilltops, in thunderstorms as lightning normally strikes the tallest objects in the area.

The intensity of the rainfall can cause surface and flash flooding, especially about low lying areas and may also lead to slips.

Fortunately, Holden said this looks to be the last severe thunderstorm warning for a while after a wet Easter weekend for the North Island.

“Things start to settle down overnight and into tomorrow,” he said.

The weather for the rest of the week in Hawke’s Bay will see a cloudy Tuesday with a few showers in the morning with light winds.

Conditions are expected to be fine and cloudy from Wednesday, with fresh southerlies dying off.

Temperatures are expected to drop late Wednesday evening with a low of 5, kick starting the colder mornings going forwards.

The rest of the week should remain fine, but with a bit of cloud, low temperatures in the mornings and fresh breezes, and a sunny Anzac weekend with highs in the 20s from Saturday.

Jack Riddell is a multimedia journalist with Hawke’s Bay Today and spent the last 15 years working in radio and media in Auckland, London, Berlin, and Napier. He reports on all stories relevant to residents of the region.