Motorists are facing difficult driving conditions and schools are shut in some areas of Scotland as Storm Eunice sweeps in bringing heavy snow.
A Met Office warning for snow is in place between 3a.m and 6p.m (0300-1800 GMT) on Friday, while a wind warning encompasses the southwest Scottish borders, including most of Dumfries and Galloway.
Snow was forecast throughout the day for most of mainland Scotland south of Inverness and Fort William and was disrupting travel on Friday morning.
The M8 was closed eastbound at junction five due to the heavy snow and Traffic Scotland tweeted that there were reports of vehicles getting stuck on the A68 near Soutra.
Bear Scotland North West Trunk Roads reported heavy snow across the northwest network, including the A83 Rest and Be Thankful, A82 Glencoe, A85 Glen Ogle, and A889 Catledge.
In Aberdeenshire, more than 30 schools were closed due to the forecast heavy snow. Ferry passengers also faced disruption on Friday due to adverse weather.
Caledonian MacBrayne said that some services were liable to disruption or cancellation at short notice due to the conditions.
Storm Eunice follows strong winds from Storm Dudley that caused significant disruption to rail and ferry services, with trees blown onto train tracks and overhead power lines.
Scotland’s Deputy First Minister John Swinney said he chaired a meeting of the Scottish Government’s resilience team.
He said that Storm Eunice “will bring the risk of snow and strong winds across most of Scotland on Friday and danger of coastal flooding in south-west Scotland.”
He added: “Please follow all advice and only travel if safe to so do.”
With more than 20cm of snow predicted on higher ground and 5cm elsewhere, Scottish Mountain Rescue warned there was a risk of “dangerous conditions” including the possibility of avalanches.
The organisation’s Vice Chairman, Kev Mitchell, said: “The weekend forecast is for very unsettled and, at times, dangerous conditions.
“With the arrival of Storm Eunice on Friday, hills will see high winds and the potential for snowfall to low levels meaning the avalanche forecast will be likely to worsen.
“Good decision-making is key in these situations and often the decision not to go, whilst correct, is the hardest one to make.”
Specialist mountain weather forecasts are predicting sustained periods of gales or hurricane-force winds on higher terrain for the next week, with snow, rain, and hail expected most days.
Mountaineering Scotland’s Safety Adviser, Ben Gibson, said: “with such extreme weather being forecast it’s important to plan your journeys around conditions rather than just going for long-held ambitions.
“Check the specialist mountain forecasts and what the Scottish Avalanche Information Service says.
“Take an honest look at your fitness and skill levels and those of the others in your party and consider whether your planned route is really attainable or whether you should adapt it or make different plans.”
In spite of the snow forecast, ScotRail said he did not expect the same levels of disruption from Storm Eunice as from Storm Dudley but has pre-emptively announced some stoppage in train services.
Glasgow and Edinburgh trains to Arbroath and Montrose to Aberdeen services would not run because sets of points on the line that allow trains to move tracks were not fitted with heaters, meaning they could freeze and get stuck.
Network Rail Scotland announced it has five locomotives fitted with snowplows to use as required, it was proactively spraying de-icer on key junctions and extra staff would be deployed to deal with any problems.
The Met Office Yellow Alert for Friday warns there was a chance of travel delays on roads.
This could mean stranded vehicles and passengers, along with delayed or cancelled rail and air travel and a slight chance that some rural communities could be temporarily cut off.
Forecasters said there was a small chance of power cuts and that other services, such as mobile phone coverage, may be affected.