MetService has issued a severe thunderstorm watch for the Coromandel Peninsula, Waikato, Taumarunui, Bay of Plenty, Rotorua, Taupo, Gisborne, Hawke’s Bay, Taihape and Wanganui regions which came into effect at 2pm this afternoon.
Localised heavy rain and hail is set to accompany these regions.
“There is a moderate risk some of the thunderstorms could become severe, producing localised downpours of 25 to 40 mm/h,” MetService said.
The watch will remain in effect until 9pm tonight.
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.
An earlier severe thunderstorm detected by the MetService weather radar moving to the east southeast and forecast to lie near Desert Road and the Kaimanawa Mountains in the Taupo, Ruapehu and Rangitikei areas has been lifted.
The National Emergency Management Agency advises that as storms approach you should:
- Take shelter, preferably indoors away from windows;
- Avoid sheltering under trees, if outside;
- Get back to land, if outdoors on the water;
- Move cars under cover or away from trees;
- Secure any loose objects around your property;
- Check that drains and gutters are clear;
- Be ready to slow down or stop, if driving.
During and after the storm, you should also:
- Beware of fallen trees and power lines;
- Avoid streams and drains as you may be swept away in flash flooding.
MetService says thunderstorms are anticipated to resume on Tuesday, with Auckland and Northland likely to experience increased shower activity.
Looking ahead, while Thursday and Friday appear more settled under a ridge of high pressure, warm daytime temperatures may spur afternoon shower activity.
“In the eastern South Island, a temperature dip today will be followed by a recovery on Wednesday, with temperatures expected to reach the low to mid-20s once again,” said Makgabutlane.
In the South Island, a ridge of high-pressure is punctuated by a frontal weather system on Wednesday and Thursday, bringing wet weather to the west and brief showers to lower and eastern parts.
A sunnier outlook is anticipated as the system moves off, providing ample sunshine in time for the end of the working week.
Tropical Cyclone forming in South Pacific
Beyond New Zealand shores, a Tropical Low near the Solomon Islands is expected to intensify into a Tropical Cyclone later this week.
“Impacts to Australia’s East Coast are expected and MetService forecasters are keeping a close eye on the path of the cyclone, especially once it moves away from Australia’s coast,” said MetService.
The season has already brought two severe tropical cyclones: Mal, which reached category 3 strength in mid-November, and last month’s Lola, which briefly became a category 5 system before its remnants caused widespread flooding and power cuts across the upper North Island.
“There’s no indication that we’ll get a tropical cyclone coming toward New Zealand at this stage, but we are flagging a moderate risk of a tropical cyclone, somewhere around that area, from around the middle of the week,” said meteorologist Stephen Glassey.