A weather warning has been issued with rain and strong winds expected across parts of the UK.
The Met Office indicated there will be “heavy and persistent rain” in the western parts of Scotland on Tuesday morning.
A band of rain is due to push southeast across Scotland, northern England and Wales.
Chief meteorologist Steven Ramsdale said: “Rain will turn heavy and persistent across western Scotland during Monday and into the early hours of Tuesday before clearing southeast during the morning.
“Widely 30 to 55m of rainfall is likely with perhaps 80mm over some of the mountains and with the rain building up overnight impacts to travel are more likely on Tuesday morning.”
Train speeds are being limited by Network Rail due to safety reasons.
Passengers are told that many routes will take longer due to the weather conditions.
A number of ScotRail services are impacted by the heavy rain.
It includes routes between Glasgow/Edinburgh and Inverness, with delays of around 35 minutes anticipated.
Delays of about half an hour are expected on routes between Glasgow and the West Highlands, as well as between Inverness and Kyle.
An area of low pressure is expected to move across the north of the UK on Tuesday night and Wednesday morning, leading to a windy day for much of the country.
Deputy chief meteorologist Rebekah Sherwin explained: “The most likely scenario is for gusts of 55 to 65mph within parts of the warning area, most likely the northern Irish Sea and parts of eastern Scotland; these are typical wind speeds for the time of year so disruption would be localised in this case.
“However, there is a chance that the deep low pressure system will bring gusts of 70 to 80mph to northern parts of the UK on Wednesday.
“Should this develop, disruption to travel and wind damage would be more likely.
“In addition, heavy rain in the northwest may make travelling more difficult.”