The weather awakens as the jet stream roars to life

Just when you’d be forgiven for thinking that the weather in the UK had gone into hibernation, it looks like there’ll be a marked change to more active weather later this week.

Much of autumn so far has been characterised by quiet weather, with above average temperatures and a lack of rainfall for eastern areas, although there has, as always, been some regional variation.

During the next few days the jet stream will roar to life, bringing with it a succession of low pressure systems, giving heavy rain and strong winds.

The wind and rain-bearing weather systems that arrive on our shores from the Atlantic Ocean are driven by the jet stream, which is a fast moving ribbon of wind high up in the atmosphere.

Over the past few weeks the jet stream has generally been sat to the northwest of the UK. It’s also been quite weak which has meant that the rate and intensity of any low pressure systems moving towards the UK has been quite low.

However, over the next few days the jet stream will roar to life, reaching speeds of around 170mph, as well as intermittently sitting across the UK.

It’s this change in position and speeding up of the jet stream that increases the rate and intensity of low pressure systems moving across us.

Scotland and Northern Ireland will be first to experience active weather. On Thursday a deep area of low pressure is likely to bring heavy rain and strong winds, gusting 50-60mph for some western coasts and hills.

A cold front will then bring a spell of rain to most places on Friday, behind which colder air will arrive with some sunshine. There’ll also be showers towards the northwest of the UK, which will be wintry across the hills and mountains.

Finally the weather has woken up!

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