A NEW state-of-the-art radar is predicted to give Scots earlier and more accurate warning of rain and floods.

The Met Office say that new scientific advancements of Scotland's rainfall radar network has been completed and will ultimately lead to improvements in the accuracy of where there will be downpours.

For the first time, the new radar can capture the size and shape of raindrops and snowflakes which helps improve the skill of weather forecasts, the forecasters say.

The project will lead to better rainfall predictions particularly in mountainous terrain in Scotland and the Scottish Environment Protection Agency say it will help cut the impact of flooding in Scotland with better predictions for forward planning.

The Herald:

The Met Office said that in the past anything from birds and insects, to hills and buildings, have interfered with the original vertical radar signal and "therefore returned false data". 

"The new upgrade means the radar can send two beams at once, one horizontally the other vertically, meaning we can visualise objects in three dimensions. By picturing the size and shape of objects, we can discount flying creatures and ground clutter from the signal and the data being fed in our weather prediction models," said. a Met Office spokesman.


The roll out was motivated by the need to replace an increasingly difficult to maintain radar network and the radar network is now more resourceful than before and there’ll be fewer engineering problems and less downtime in future.

The improvements have been made to the four weather radar systems in Scotland including stations on the Isle of Lewis and Munduff Hill, Perthshire.

The new system was developed in-house by Met Office engineers, using what it described as "unparalleled levels of skill and expertise" meaning it has a number of unique capabilities not found on commercial radar.

The new radar delivers five time more data, with almost a terabyte being received from each radar over the course of a year.

The Met Office can now record 1.8 million rainfall observations per hour per radar and can identify swarms of insects or flocks of birds over 25 miles away.

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Pat Boyle, head of strategic relationships for devolved administrations at the Met Office said: “Weather radar provides the only means of measuring the spatial extent and distribution of rainfall over a wide geographical area.

"The most intense rainfall events are often highly localised and can therefore be missed or under-sampled by rain gauge networks, and whilst their occurrence can be forecast with skill, it is often not currently possible to forecast their exact location.

"Radar therefore provides a crucial input to short-range weather forecasts (nowcasts) of precipitation rate, and improves the skill of weather forecasts when it is assimilated into numerical weather prediction models.”

David Pirie, Scottish Environment Protection Agency's evidence and flooding director said; “We’re delighted to see the completion of this project.

"It will enhance our joint capability in forecasting river and surface water flooding events with improved accuracy and longer lead time. It is an essential step in achieving our aim of reducing the impact of flooding in Scotland”.

The stations will include Doppler technology which allows the radars to observe how the rainfall is moving, including a wind measurement.

The systems also now include 'dual polarisation' which allows the radar beams to travel both horizontally and vertically through the atmosphere means that the Met Office can now examine the shape of raindrops.

This, in turn, provides understanding the structure of the raindrops and helps forecasters accurately pinpoint the difference between rain, hail and snow.