Thousands of homes in Arran, Kintyre and Wigtownshire without power
Thousands of Scottish homes are still without power, three days after losing supplies due to severe weather conditions.
Around 3,500 homes on Kintyre and 1,500 on Arran are still waiting to be reconnected.
A further 300 homes remain without electricity in Dumfries and Galloway.
Engineers' efforts to restore supplies have been hampered by a weekend of snow, blizzards and heavy winds.
Residents in parts of Arran fear they will remain off the national grid until Friday as areas of Scotland continue to be hit by severe weather. In some areas there were 15ft snow drifts.
Heavy snow and ice brought down power lines in Kintyre on Friday which blacked out a huge area over the weekend. At the peak of the problems around 18,000 homes were without power.
An 80-year-old suffering from hypothermia has been airlifted from Pirnmill in the island's north-west to Crosshouse Hospital in Kilmarnock.
Local hotels supplied with generators have been acting as emergency centres.
Kinloch Hotel manager Fraser Hendry said: "We've been told it could be Friday before we get the supply back."
Numerous schools are closed, including all schools on Arran, all Argyll and Bute primary schools south of Tarbert and more than a dozen schools in Dumfries and Galloway.
Travel problems have eased after many roads were closed on Friday and Saturday, while rail, ferry and air travel was also disrupted.
The A3 Campbeltown road has now reopened, however a number of roads in the Highlands, Tayside, Grampian and Dumfries and Galloway remain closed.
Scottish Power said the main areas affected in south west Scotland on Sunday were in Wigtownshire and Barrhill, with nearly 3,000 homes off supply at the start of the day.
Scottish Power said it hoped to restore power to most customers on Sunday night either by the main lines or by generator.
It added: "The conditions in the area since Friday have been extremely difficult and our engineers have experienced significant challenges caused by the extreme weather.
"In order to reconnect properties we have seen engineers left stranded in their vans overnight and walking for miles in snow drifts of up to 10ft attempting to reach faults."
Scottish and South Energy (SSE) said it expected to return power to the majority of homes on Arran by the end of Sunday, although local damage and access issues may mean customers in more rural areas would still be without power overnight.
"For Kintyre, we expect to restore a large number of customers in the south of the peninsula during today, centred around Campbeltown," SSE said.
"Unfortunately, due to continuing severe conditions further north hampering access, we expect customers in more rural areas to be off supply overnight."
Kinloch Hotel is among several heated rest centres set up across the island and has acted as an emergency surgery for the local doctor as well as power company employees attempting to restore the electricity supplies.
Mr Hendry told BBC Scotland: "The bigger villages like Brodick and Lamlash are now fairly clear, but we on the west of the island have borne the brunt of it.
"A lot of people have been walking down for their lunch or dinner and a group of students who were stranded here from Cambridge University helped us deliver supplies to the elderly, but the problem is the smaller hamlets."
The local grocery store at Blackwaterfoot was almost now empty, but the hotel manager said a rescue helicopter had delivered supplies three times during Saturday alone.
"But every single electric pole in the village has been flattened and we are running out of diesel for the generator having already borrowed from local farmers," said Mr Hendry.
In addition to mobile generators already ferried to the island, five more were ordered and five mobile catering units were organised on Arran and three in Kintyre.
Neil Young, a fireman at Lamlash on Arran, said about 100 people a day had been taking advantage of his fire station's offer of hot refreshments and shower facilities.
A spokeswoman for Strathclyde Police said that the elderly woman airlifted from Arran to Kilmarnock is in a stable condition.
The coastguard used boats from Troon and Arran to deliver supplies and offer assistance where needed.
A spokesman for Belfast coastguard, which covers the area, said: "We've got a 4x4 helping and boats are taking blankets and provisions from the mainland to places like Lochranza, which is cut off by road."
SSE is also attempting to clear the roads to reach three steel towers that have collapsed under the weight of ice on the conductors near Crossaig in Kintyre.
Generators were taken to Campbeltown on Saturday on a special sailing of the MV Hebridean Isles from Kennacraig further north along the peninsula.
Residents were told to conserve their fuel supplies to help ease the burden on the mobile generators, while fuel stations have been told to supply "priority vehicles" only.
On Sunday, the Met Office issued yellow warnings for ice in Strathclyde, South West Scotland and Lothian and Borders.
It said lying snow in many areas would melt on roads and pavements by day, refreezing by night to give icy patches.
Snow blowing off fields in strong to gale force winds will affect some roads on Sunday night, especially over high ground.
The warnings are valid until 09:00 on Monday.