Gusts of up to 84mph and lightning strikes left 12,000 properties without power at the height of Storm Abigail.
About 1,300 customers remain without electricity after 30 faults affected the Western Isles, Shetland, Skye, Colonsay, Argyll and Angus.
Every school on the Western Isles and Shetland is closed for safety reasons.
The high winds and rain have been followed by wintry showers which have affected driving conditions on the A9 at the Slochd in the Highlands.
Hills, including mountain tops in the Cairngorms and Lochaber, have had fresh falls of snow.
SSE Power Distribution said engineers had restored power to most of the 12,000 customers affected by power cuts and its engineers were working to reconnect 1,300 still without power.
The Met Office had an amber “be prepared” warning in place on Thursday for northern and western Scotland, but this has since been downgraded to a yellow “be aware” warning.
Ferry operator Caledonian MacBrayne said 23 of its 26 services on the Clyde and Hebrides network have been disrupted.
A number of Northlink’s Northern Isles ferry services have also been affected. Early morning sailings between Stromness and Scrabster were cancelled.
On Thursday, a ferry travelling from Skye to Raasay was prevented from docking for three hours due to stormy conditions.
The journey would normally have taken 20 minutes, but CalMac confirmed the vessel – which had five Portree High School pupils on board – was at sea for longer than usual.
Lochaber Mountain Rescue Team have rescued a hillwalker who attempted to climb Ben Nevis via Observatory Gully as the weather closed in.
After the operation on Thursday evening, the team posted on social media that “on the scale of difficulty this route is certain death”.
The casualty was found with chest injuries and lowered to safety at about 20:30.
The team added: “A very difficult rescue in atrocious weather with a very good outcome.”
Forecasters warned of winds gusting to up to 90mph, heavy rain, lightning and large waves may affect coastal areas.
The amber warning covers from 18:00 on Thursday to midday on Friday, and yellow warning from 18:00 on Thursday to 23:00 on Friday.
Further yellow warnings have been issued for central and southern Scotland for Saturday to the early hours of Monday and warn of heavy rain.
The Scottish Environment Protection Agency has warned of the risk of flooding over the next few days.