Simon King
BBC weather presenter and meteorologist

Storm Lilian is more typical of an autumn storm,
not something we usually see in August (though we did have two named storms
last August as well – Antoni and Betty).

Lilian is a deep area of low pressure that formed
quite rapidly on Thursday night.

In meteorology, low pressure systems are the ones
that give us the wet and windy weather.

If pressure is particularly low, the winds around
it will be stronger.

On a pressure chart that’s visualised by the white
lines…the closer they are, the windier it is.

These areas of low pressure have been directed to
us by a fast wind high in the atmosphere flowing across the Atlantic.

This wind – the jet stream – is also the thing that can either strengthen or weaken
weather systems at the Earth’s surface.

Over the last few days, the jet stream has been
particularly active bringing the remnants of ex-hurricane Ernesto to our shores
as well as creating Storm Lilian.