Forecasters are expecting the storm - the third named storm of the year - to bring gusts of up to 80mph in northern Scotland.
Motorists are being warned of potential disruption, as a band of snow looks set to sweep across Cumbria - with a second warning already issued for the weekend.
Today will be the last day of mild conditions before a cold snap forecast to last until Christmas grips the UK.
The Met Office said the high winds were expected to damage buildings and cause flying debris, as well as power cuts, severe travel disruption and risky waves.
Snow showers will affect northern Scotland later on Thursday, with the risk extending across more of Scotland, Northern Ireland, Wales and western parts of England on Friday.
"A spell of heavy snow is possible over some central parts of the United Kingdom during Sunday", reports the Met Office.
Between 10 and 20cm of snow can be expected over hills and mountains. There'll be some showers of sleet and snow over Ulster on Sunday - elsewhere it will be cold and bright with severe frost after dark.
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Sunday's weather warning is in force from 04.00 on Sunday until 23:55.
The yellow level alert is in place from midnight on Friday until 6pm on Saturday.
'Overnight, the main feature will be the increase in wind as Caroline starts to come in towards the end of the night. "There is a good chance that power cuts may also occur".
The Met Office has issued an amber "be prepared" weather warning for northern Scotland on Thursday.
A North Sea platform shut down production due to safety fears over weather conditions caused by Storm Caroline.
Brian Gaze, forecaster for Weather Outlook, said: "Colder easterly air expected from as far away as Siberia means minimum temperatures as low as -16C could be seen this winter in Scotland, with -12C even in sheltered parts of southern England".