Red warnings are issued when it is highly likely that the weather will cause a high level of impact, and this warning is only the second red warning for snow that the Met Office has issued since 2011.

Heavy snow showers have been affecting many parts of the UK throughout this week, with amber and yellow warnings issued, as cold, wintry weather has moved in from the east.

Across parts of Stathclyde, Fife, Lothian and Borders, further heavy snow is forecast this afternoon and overnight into tomorrow, which is expected to result in significant disruption to travel, including roads becoming blocked by snow and some communities becoming cut off. Long travel delays and cancellations to public transport services can also be expected, as well as loss of power supplies and other services. A red warning for snow has been issued for this area.

Andy Page, Chief Meteorologist with the Met Office, said: “Snow showers already affecting the area will become heavier and more prolonged later on Wednesday and through the overnight period. 5cm of snow could fall within an hour in places and lying snow could reach 20-30 cm or possibly 40cm in a few places by mid morning on Thursday. Strong easterly winds will lead to significant drifting of lying snow”

“By Thursday morning, parts of England and Wales are forecast to see a more widespread area of snow associated with Storm Emma. This snow will likely become heavy through the afternoon across parts of southwest England and Wales, allowing 10-20cm of snow to accumulate quite widely here.

“Parts of south west England and Wales could also see freezing rain for a time on Thursday night – a relatively rare weather phenomena in the UK. This can result in a high level of impact as ice forms very rapidly on surfaces, leading to severe risks affecting transport and power networks”.

Freezing rain starts as snow, ice, or hail, which melts as it falls through a layer of relatively warmer air before refreezing in a layer of colder air. The rain droplets become 'supercooled' and are close to or below freezing on impact on surfaces such as roads, pavements and power cables.

The Met Office has been working extremely closely with our partners in road, rail, air transport and emergency services to ensure they have the latest forecast information and to help minimise the impacts on members of the public.

Dr Thomas Waite, of Public Health England’s Extreme Events team, said: “When the wind drives temperatures even lower, the risks to health can increase as even people not normally at risk from cold related illness can feel the effects more. This is why it’s so critical to keep warm; a good way is to keep homes heated to at least 18C.

“In weather like this our bodies have to work harder, older people, young children and those with long term conditions like heart and lung diseases, can really struggle to cope in such low temperatures. So do keep an eye on those at risk, wear several thin layers instead of fewer thicker ones and if you’re able, consider clearing paths of snow and ice. Staying warm will help you stay well – and that’s vital in exceptional weather like this.”

Highways England’s Head of Road Safety, Richard Leonard, said: “Gritters are out treating our routes around the clock but it is still important to drive to the conditions when snow is forecast.

“If you need to travel in the morning, make sure you keep your distance and reduce your speed because, even in conditions that seem normal and when the snow is not settling, it can be slippery if ice patches have formed, or where fresh salt has not been worked into the carriageway.

“Drivers should plan their journeys, monitor weather reports and pack a snow kit of blankets, food, water and a shovel if they really need to travel.”

Transport Minister for Scotland, Humza Yousaf, said:  “Whilst the worst of the weather is predicted to impact the east of Scotland, the rest of the country is also likely to face wintry conditions, so I’d ask travellers to consider if they need to make their journeys during the amber warning periods. If you do choose to travel during those times, you are very likely to face delays and disruption.

“You can use the Traffic Scotland mobile website or the @trafficscotland twitter page to access the most up to date travel information and to check if your route is affected.

 “It’s inevitable that these conditions will also impact on other modes of transport, so if you’re planning to travel by rail, ferry or plane, you should check ahead with the operator to find out if your service has been affected.”

You can find out the current forecast in your area using our forecast pages and by following us on Twitter and Facebook, as well as using our mobile app which is available for iPhone from the App store and for Android from the Google Play store.