The yellow - "be aware" - severe weather alert has been issued from 8pm until 9am tomorrow.
It covers much of the mainland north of the Central Belt away from the east coast.
A Met Office spokeswoman said: "Icy patches will form across some north-western areas of Scotland, initially over higher roads this evening but more generally overnight and at first on Friday.
"In addition, blustery showers will turn progressively more wintry, with slight accumulations of snow, these mainly on hills above 200-300m.
"This wintry combination, will bring tricky driving conditions, particularly for the higher-level roads.
"As frontal systems clear, we will see a colder air mass than for some time, crossing Scotland from the west.
"This will be bringing some mainly low-key wintry hazards, although being a showery set-up, some places will stay dry, especially east of the mountains."