The Met Office has warned that Storm Dave could bring heavy snow and gale-force winds, with power cuts also possible in parts of the UK.
An amber weather warning for wind came into place for parts of northern England, Scotland and Wales earlier on Saturday, and the Met Office has now said the storm will "continue to deepen" in the coming days.
The amber alert warns flying debris could lead to "injuries or danger to life".
Heavy snow and gale-force winds will also bring disruption, with winds of up to 66mph already being recorded in Capel Curig, north Wales.
Parts of Lancashire, North Yorkshire, Northumberland, north Wales and Scotland are covered by the amber warning, which came into effect at 7pm and is due to remain in place until 3am on Sunday.
The Met Office said that "while some uncertainty remains in the exact track and shape of Storm Dave, a spell of strong southwesterly winds is expected".
Meanwhile, four separate yellow weather warnings from the Met Office came into force on Saturday afternoon:
• An alert for wind covering northern England, parts of Scotland and part of Wales is active until 7am tomorrow
• A separate warning for wind across the whole of Northern Ireland is in place until 3am
• The whole of mainland Scotland and a part of northeast England also faces a yellow warning for wind until 12pm tomorrow
• A yellow alert for snow applies to the Scottish Highlands until 3am
Storm Dave will be at its worst later on Saturday, but will weaken on Sunday as it blows into the North Sea.
Travel disruption on the roads - as well as on rail, air and ferry services - is possible.
Large waves could cause dangerous conditions along the coastline, and there may be 80mph gusts in exposed areas.
Meanwhile, the Energy Networks Association (ENA), which represents electricity network operators, said on Saturday: "The storm has the potential to affect local power infrastructure, increasing the risk of a power cut and fallen power lines.
"Network operators are increasing staffing for operational teams, and moving spare equipment to where the weather is expected to be most disruptive, so it's ready to use if needed."
Met Office meteorologist Greg Dewhurst said that once Storm Dave passes, parts of the UK will have a spell of warm weather.
He predicted "heavy snow" would form across parts of the Highlands through Saturday afternoon, evening and night and "as much as 20-30cm (8-12 inches) could fall over the higher ground, and 5-10cm (2-4 inches) over lower ground".
But warmer air arrives from Europe after Easter Monday, bringing higher temperatures through Tuesday and into Wednesday, he said.
England and Wales could "see temperatures rising to the low 20s, with highs around 20C (68F) or 21C (70F) on Tuesday, and possibly 23C (73F) or 24C (75F) come Wednesday".
Southeast England could enjoy the best of the sun on Wednesday, "where 23C and 24C is most likely".
Scotland's First Minister John Swinney warned of "really quite challenging conditions" later on Saturday and urged people to "follow all of the advice that's available and to make sure they stay safe".
George Fiddes, from Transport Scotland, said motorists "should check their planned routes before setting off".
Some areas could also experience power cuts.
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Earlier this week, the RAC predicted that it could be the busiest Easter on the roads since 2022 - with ABTA estimates indicating two million people were planning to travel abroad.
In Scotland, Network Rail has warned that the East Coast Main Line and services on the Ayrshire coast could be most affected by the extreme weather.
(c) Sky News 2026: UK weather: Met Office warns of heavy snow and power cuts as Storm Dave hits
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