Covering period of Monday 15 – Friday 19 January – The hot and sunny start to 2024 is put on pause early this week, with MetService forecasting heavy rain and possible downpours over parts of the North Island, while the South Island experiences a cool change from the high temperatures last week.
A Heavy Rain Warning was issued this morning (Monday) for central western areas of the North Island. Additionally, a Severe Thunderstorm Watch was issued for the northeast of the North Island from the Coromandel Peninsula through Rotorua to the eastern ranges of Bay of Plenty, and a Heavy Rain Watch for those eastern ranges until tomorrow morning (Tuesday).
MetService Meteorologist Clare O’Connor says: “While the first two weeks for 2024 were overall quite dry for the North Island, we are seeing a wet week ahead. The Severe Thunderstorm Watch for the upper North Island today in particular could see downpours of 25-40mm/h within the watch area, so residents should be prepared for heavy falls later today.”
Down south, there has been a sharp change from the weather of last week, in particular the temperature: Invercargill’s forecast maximum temperature today (Monday) is a mere 14°C.
Summer will return though; Tuesday heralds a sunny day for the South Island and most of the North Island as a ridge takes hold of the situation again, pushing the rain northwards. These conditions continue on Wednesday, but by Thursday the rain returns – this time for central Aotearoa/New Zealand.
“What’s left of the band of rain from Monday makes its way over to the west of Aotearoa, bringing more rain to western South Island areas north of about Hokitika, but Wellington and the Kapiti Coast should plan for wet weather in the second half of the week also.” O’Connor notes.
The final act of the wet week arrives on Friday: a low pressure system forming in the Tasman Sea drags warm, moist air over the South Island. MetService’s Severe Weather Outlook is indicating a high confidence of heavy falls of rain along the South Island’s West Coast, and Severe Weather Watches and Warnings may follow in the lead up to the arrival of this system.
Understanding MetService Severe Weather Warning System
Severe Thunderstorm Warnings (Localised Red Warning) – take cover now:
This warning is a red warning for a localised area.
When extremely severe weather is occurring or will do within the hour.
Severe thunderstorms have the ability to have significant impacts for an area indicated in the warning.
In the event of a Severe Thunderstorm Red Warning: Act now!
Red Warnings are about taking immediate action:
When extremely severe weather is imminent or is occurring
Issued when an event is expected to be among the worst that we get – it will have significant impact and it is possible that a lot of people will be affected
In the event of a Red Warning: Act now!
Orange Warnings are about taking action:
When severe weather is imminent or is occurring
Typically issued 1 – 3 days in advance of potential severe weather
In the event of an Orange Warning: Take action.
Thunderstorm Watch means thunderstorms are possible, be alert and consider action
Show the area that thunderstorms are most likely to occur during the validity period.
Although thunderstorms are often localised, the whole area is on watch as it is difficult to know exactly where the severe thunderstorm will occur within the mapped area.
During a thunderstorm Watch: Stay alert and take action if necessary.
Watches are about being alert:
When severe weather is possible, but not sufficiently imminent or certain for a warning to be issued
Typically issued 1 – 3 days in advance of potential severe weather.
During a Watch: Stay alert
Outlooks are about looking ahead:
To provide advanced information on possible future Watches and/or Warnings
Issued routinely once or twice a day
Recommendation: Plan
