Flying under the RADAR

By Lisa Murray, Communications Meteorologist.

The term RADAR stands for RAdio Detection And Ranging and was coined in 1940 by the United States Signal Corps, although it was German physicist Heinrich Hertz who showed that radio waves could be reflected from solid objects, in around 1886. During World War II, radar technology developed rapidly and has since become an essential tool in meteorology, as well as in other areas such as air traffic control.

Significant heavy rain & gales 5-8 May

By Peter Little, MetService Meteorologist

As a slow-moving ridge of high pressure departs to the east today, a deep northwesterly flow spreads onto New Zealand ahead of a trough.

Ensemble Forecasting

The wisdom of the crowd Wisdom of a crowd At a county fair in Plymouth, England, in 1906, several hundred fair-goers entered a contest to guess the weight of an ox. The average guess was extremely close to the true weight of the beast – even though some of the individual estimates were wildly off the mark!

Severe weather expected on Sunday and Monday


An intense weather system that has already brought severe weather to parts of Australia has been moving slowly east over the Tasman Sea towards New Zealand. This system has brought heavy rain to the southwest of the South Island this morning. Around 400mm of rain have accumulated in some parts of Fiordland.

A tempestuous end to April - update

This blog contains the latest on the wild weather heading our way this long weekend. Read on for details of the current severe weather outlook and watch, as well as the latest chilly temperature forecasts for Monday and Tuesday.

Severe weather

A tempestuous end to April

By Emma Blades, MetService Meteorologist

Out over the Tasman Sea, a warm and moist weather system is gradually making its way southeast towards New Zealand. Meanwhile cold weather is brewing in the Southern Ocean – preparing to blast the warm air away.

First the wet weather

A satellite image for every occasion

By Rebekah LaBar, MetService Meteorologist Satellites are one of a meteorologist’s best tools. Satellite images can tell us where weather systems are and how fast they are moving. They can also often help us distinguish between many things such as thick and thin clouds and high and low clouds, as well as detecting snow, fog, volcanic ash, smoke, thunderstorms, and much more.

Jack Frost to make an appearance

By Rebekah LaBar, MetService Meteorologist

The low-pressure system that brought cold weather, snow, and thunderstorms to New Zealand is pulling off to the east today. An unsettled southwest flow will continue to dominate the weather this week, although temperatures will gradually rise as we head towards the weekend and the recent snowfalls will start to melt.

Cold blast to start the week

A deep upper-level trough of low pressure is moving over the South Island of New Zealand today, while an associated surface low lies to the southeast. The trough is dragging up cold air all the way from Antarctica in our first significant cold outbreak of the year that will continue to bring snow to parts of the South Island and high elevations of the North Island today and tomorrow. Thunderstorms with small hail are also possible. As the low-pressure system strengthens, it will also bring strong winds and high swells to coastal areas of especially the South Island.

Snow to low levels over the South Island on Monday

A burst of cold air originating from the Antarctic ice sheet is expected to affect New Zealand on Monday and Tuesday. Unseasonably cold temperatures, strong winds and snow to low levels are expected over the South Island where this event is likely to have a high impact. Snow is forecast down to around 200 to 300 metres in Fiordland, Southland and Otago but 400 to 500 metres in Canterbury. Hail and snow flurries could penetrate even lower. People in places such as Invercargill and Dunedin may see some snowflakes that melt as they hit the ground.