Scotland’s first storm of 2015 will be fiercer and come sooner than previously forecast the Met Office has warned.
And while the central belt is likely to escape the worst of the weather, but could experience gusts of up to 70 mph.
The alerts came after up to 40 mm of rain fell in some local areas tonight.
Forecasters upgraded their severe weather warning for the Highland and Islands to amber - “be prepared” - for 10 p.m. tomorrow until noon on Friday.
Most of the remainder of the country remains on yellow alert - “be aware” - for that period, with wind gusts of up to 70mph.
The Met Office said “significant impacts” were likely from tomorrow night’s storm.
Its spokesman said: “The public should be prepared for the potential for disruption to transport as well as power supplies and the possibility of structural damage.
“Very large waves may also lead to dangerous conditions along some coasts.”
The storm, which had been forecast to arrive at noon on Friday, is being caused by very cold air over the United States combining with 250 mph jet stream winds at high altitude - compared to the usual 150 mph at this time of year.