THE public were given little warning of the ferocity of the storms that ravished swathes of Scotland's Central Belt yesterday as forecasters scrambled to update their advice in the face of rapidly worsening conditions.

The Met Office, which provides forecasts to the Scottish Government, changed its weather warning from "amber" to "red" at 8.14am as it became clear that the winds bearing down on the west of Scotland were stronger than had been anticipated. But that was only after gusts of 91mph had been recorded at Glasgow Airport.

Two hours later, as the storm drove east, wind speeds of 102mph were recorded at Blackford Hill in Edinburgh, the third highest on record.

The situation contrasted sharply with the storms of December 8 last year, which were preceded by clear warnings from the Met Office and the Scottish Government a day earlier to avoid all travel where possible.

In the event, although the December storm saw a slightly higher maximum wind speed, yesterday's storm had a far more devastating impact as the highest winds were concentrated in urban areas of the Central Belt. In Edinburgh, the highest gusts were 25mph faster than those recorded in December.

A major difference between the two weather systems was the speed with which yesterday's high winds developed, helped by a meteorological phenomenon known as a "sting jet", Helen Chivers, a spokeswoman for the Met Office said.

The phenomenon, which is responsible for some of the most damaging storms in Europe, is characterised by a hook-shaped cloud in which a jet of accelerating air descends from the cloud head, picking up speed as it goes. It is thought to have added around 25mph to yesterday's wind speeds, according to some forecasters.

"It is a factor. It happens very rapidly, hence you end up with a very rapid increase in wind speeds and, equally, it dies down again very quickly. So we had two to three hours of very strong winds in a very narrow area," Ms Chivers said.

"It's the timing in a weather system that can be difficult to predict. Sting jets are not common and it's being able to time that very rapid increase in wind speed where you know you have the atmospheric conditions for that to happen. It doesn't happen every time you get a depression."

The first "yellow" warning, advising the public to be aware of potential problems, was issued by the Met Office on Sunday but upgraded to an amber warning on Monday lunchtime, with the public advised to "be prepared".

The warnings are graded according to the likely impact on houses, people and travel networks rather than triggered simply by wind speeds, the Met Office said.

The latest "red" warning, advising the public to take action, was issued as forecasters confirmed the storm would be concentrated over densely populated areas in central Scotland, a spokesman said.

That left the Scottish Government with little time to update the public.

An announcement was made by its agency, Transport Scotland, on Monday afternoon but by the time the next press release was issued after noon yesterday, the worst effects of the storm had passed.

A Government spokeswoman said yesterday a meeting of the Multi-Agency Response Team, involving the Scottish Government and emergency services, had been held on Monday afternoon after the amber warning was received from the Met Office.

"Both the Scottish Government Resilience Room and the Multi-Agency Response Team were operating before the Met Office Red warning this morning," the spokeswoman said.