Arctic air causes -9C temperature change as Met Office forecasts colder spell

An Arctic chill will send temperatures across the UK plummeting in the next week, forecasters say.

The mercury is anticipated to drop by as much as 9C - some 40% - by Wednesday September 24 due to the bitter low pressure moving southwards. The Met Office has confirmed a colder spell looms, following balmy highs for the time of year of 22C this week, recorded in Hull and Rostherne, Cheshire.

But on Wednesday afternoon, 13C is forecast in Hull and it'll be even colder elsewhere, with 10C expected across Derbyshire, 11C anticipated in Northamptonshire and parts of Scotland braced for 8C.

Jo Farrow, meteorologist with NetWeather, writes on the site's blog: "Colder air will be brought south over the UK from the Arctic, replacing the warmer air of this week. This high pressure will slowly edge towards Scandinavia, toppling towards the Baltic States. Ahead of the high, colder air will be dragged into NE Europe, but behind the high, milder air will move up the Atlantic to the northwest of Scotland.

"This week, southern Britain will have temperatures in the high teens rising into the low 20s, even up to 25C for SE England by Friday. Through the weekend and for next week, the UK will be in a colder air mass which could bring the first frosts by night in the north, morning fog for commuters and a real autumn chill if the wind picks up."

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UK weather maps are mostly a green hue next week, indicating it will feel cold and windy in places. The Met Office recognises this change, warning Brits of an unsettled weekend and frequent patches of fog and frost during the week.

"The best of drier spells will be in the north and northwest where some fog and frost patches are possible, but there will be spells or rain or showers in south and eastern areas, near to an area of low pressure. It will also turn colder, as a northerly flow becomes established for a time," the Met Office's site reads in relation to Monday September 22 to Wednesday October 1.

There has been significant rainfall this week, including more than 40mm in just a few hours across rural north Wales on Wednesday. There is still a risk of flooding in some counties, such as Cumbria in the Northwest of England, as river levels are nearly saturated.

But, despite the cold temperatures expected, little rain is anticipated in the coming days. Today will be dry, especially in the east, and Friday will be dry across southern counties, including Greater London and the surrounding areas.