Thunderstorm watches for Auckland and Northland, Digi Mart USA News (Auckland, New Zealand): Thunderstorm watches have been issued for the top of New Zealand’s North Island, with downpours of 25-40mm per hour possible. Northland’s watch is in effect until 9pm today, while the watch for Auckland and Great Barrier Island runs from 11am to 9pm.
MetService said the watches carry a moderate risk of severe thunderstorms with localised downpours of up to 40mm per hour. “Rainfall of this intensity can cause surface and/or flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips.” Driving conditions will also be hazardous, with surface flooding and poor visibility in heavy rain, the agency said.
Heavy rain watches for Northland, Auckland, Great Barrier Island, Waikato, Waitomo, Taupo, Taranaki, Taumarunui and Tongariro National Park start at 9pm and last until 1am Wednesday. The weather comes as muggy nights are forecast for the North Island, as a “subtropical air express” brings warm, moisture-laden Pacific air.
MetService says a humid northerly flow will gradually spread across the island at the start of this week.
Meteorologist Paris Marshall told the Herald that Whakatāne and Whitianga were forecast to have “sweltering” overnight lows of 17C. Marshall said the incoming weather was being driven by a separate system from the Tasman Sea.
“It’s just been whirling away for a while, collecting all this moisture from the ocean,” she said, adding that it had moved over New Zealand, which was unfortunate for areas that had already experienced wet weather.
The incoming weather follows a dramatic Saturday afternoon when thunderstorms brought torrential rain and large hailstones to parts of the North Island. In Auckland, large hailstones damaged vehicles in the Waitākere Ranges, while heavy downpours caused flooding on the North Shore.
The storms also disrupted flights, caused power outages and delayed the Auckland FC-Wellington Phoenix match. MetService detected more than 5,000 lightning strikes on Saturday, mostly across the North Island.
Meanwhile, severe thunderstorms swept through parts of Canterbury yesterday afternoon, prompting a warning for the Hurunui district. Marshall said there was a moderate risk of thunderstorms across central and northern parts of the North Island today, and the forecast could change as the weather system develops.
Further thunderstorms are possible on Tuesday, particularly in Northland, Auckland, Coromandel and Bay of Plenty, with heavy rain also possible in the lower North Island and Nelson-Tasman. The South Island will largely escape the humidity until Wednesday, when the system is expected to “push off” from the North Island, bringing wetter and muggier conditions further south.
