Motorists are facing difficult driving conditions as heavy rain has led to flooding in some parts of Scotland.
Rail services have also been affected by the weather, with train speeds limited in many areas on Friday due to heavy rain overnight.
A Met Office amber alert for heavy rain in parts of Dumfries and Galloway as well as the Scottish Borders was in force until midday, while yellow weather warnings of snow and ice cover other areas of the country.
Forecasters said around 40-50mm of rain was expected in the amber warning area, with 60-70mm possible in upland locations, with the potential for fast-flowing or deep floodwater, causing danger to life.
The Scottish Environmental Protection Agency (Sepa) has issued 10 flood alerts and 27 flood warnings across Scotland.
River levels were expected to rise as a result of heavy overnight rain, with levels peaking during daylight hours on Friday.
Dumfries and Galloway Council urged people to take care, and tweeted: “We’ve seen a lot of rain overnight. There’s a lot of surface water on roads across D&G. Please be safe out there if you’re travelling.”
Roads affected by flooding on Friday morning included the A90 northbound Stonehaven-Muchalls in Aberdeenshire, A90 southbound at Stracathro in Angus, with flood units responding in the area, and the A76 Sanquhar carriageway in Dumfries and Galloway, where Traffic Scotland said conditions are “extremely difficult”.
Police in Dumfries said they were expecting flooding in Whitesands, Dockhead, and Dock Park overnight and on Friday.
Network Rail said the heavy overnight rain “means we need to limit train speeds in many areas of Scotland for everyone’s safety”.
The West Coast Main Line is closed between Lockerbie and Carstairs due to flooding at Beattock, Dumfries and Galloway, following “extreme overnight rainfall”.
Network Rail Scotland tweeted: “We’re dealing with over 20+ flooding issues across Scotland’s Railway, causing severe disruption.”
ScotRail is only running trains on seven routes due to the weather conditions, but it said it hopes to reinstate other services later in the day.
As of 11am on Friday, it was only able to operate trains on the Cathcart Circle, Glasgow Central-Neilston and Newton, Bathgate-Dalmuir, Edinburgh-North Berwick/Dunbar, Edinburgh-Tweedbank, Inverness-Wick and Kyle, and Aberdeen/Inverness-Perth routes.
The Met Office said the deadly bomb cyclone that sent temperatures plunging in the US over Christmas is causing the unsettled weather in the UK.
A yellow weather warning for heavy rain is in effect in Scotland until 2pm on Friday, covering central Scotland, Tayside and Fife, south-west Scotland, Lothian and Borders and Strathclyde.
A yellow warning of rain for Northern Ireland expired at 10am on Friday.
Meanwhile, a yellow warning of snow and ice covers northern Scotland, apart from Orkney and Shetland, until 9pm on Friday.
Police Scotland said there is a high risk of disruption and urged people to plan ahead and drive to the conditions if they have to travel.
The Scottish Government said the Multi-Agency Response Team will monitor conditions throughout the amber warning period.
Superintendent Stewart Mackie, of Police Scotland’s Road Policing Division, said: “An amber weather warning has been issued for heavy rainfall and flooding across southern Scotland, and people should consider delaying any travel plans until conditions improve.
“If your journey is essential, please plan ahead by making sure you have sufficient fuel and supplies in your vehicle, a charged mobile telephone and always drive as the conditions allow.
“Be aware road closures and travel delays are likely, with potential disruption to public transport services.”
Vincent Fitzsimons, flood duty manager at Sepa, said: “Heavy rain overnight into Friday has resulted in flooding in parts of southern and central Scotland. Surface water impacts have already caused significant disruption to the transport network, with roads and railway lines flooded.
“River levels are also rising fast and are expected to peak later in the afternoon, with flooding of properties possible. The main areas of concern are riverside communities in Dumfries and Galloway and the Borders such as Dumfries, Hawick and Peebles. Regional flood alerts and local flood warnings are in place.
“Many people are likely to be travelling ahead of Hogmanay and are advised to plan ahead for their journeys. All those in affected areas should consider steps they need to take to be prepared and stay safe. Anyone out walking should also be extra cautious, even around small watercourses. More advice and updates are available on floodline.sepa.org.uk.”