Traders and residents in the Whitesands area of Dumfries, through which runs the River Nith, have suffered from countless floodings over the years.
The weekend downpour resulted in the Nith rising by 14ft as snow melted on nearby hills, which together with the rain flooded hundreds of acres of farmland.
It flooded the town centre yesterday after water levels rose from early morning, forcing police to seal off Whitesands and put traffic diversions in place.
The deluge follows heavy snow on Friday, which paralysed the area and caused traffic chaos.
A spokesman for Dumfries and Galloway Police said: "The road was closed in the early morning and all cars were moved off. It rose very quickly, with a combination of the rain, melting snow and the high tide, which was at around midday."
Shopkeepers and householders put together barricades and sandbags to try to prevent the water breaching premises but several pubs and shops were soon under water.
The flooding was expected to last throughout the night and a watch was being kept for the coming high tide.
A Scottish Environmental Protection Agency spokesman said yesterday: "River levels at the Whitesands have now peaked and the flood water is starting to recede.
"Levels should continue to fall during the afternoon into the evening and it is expected the river will be back in bank early this evening."
Flooding has occurred from the foot of Friars Vennel along Brewery Street and the Whitesands car park to Bank street.
Other rivers in the area including the Annan, Urr, Esk and Dee were in full spate and low-lying farmland was under several feet of water in many areas.
Several roads in the Stewartry were closed because of deep flood water, including the A712 Crocketford to Balmaclellan Road and the B794 link road between the A712 and the A75, through Kirkpatrick Durham.
Warnings were also issued for villages along the Solway coast, where big tides have been backed by gale-force winds.
Across the country, flood alerts were in place for Argyll and Bute, Ayrshire and Arran, as well as Dundee, Skye, Wester Ross and the Western Isles.
In the Borders, flood warnings were issued for the Ettrick Valley, around Hawick and Eddleston Water in Peebles. Three flood warnings were also in place on Tayside, affecting Crief and Bridge of Earn.
Motorists were hit by torrential rain and hail in Glasgow and the west of Scotland yesterday morning but there were no reports of any major incidents.
Meanwhile, a fishing boat with three people on board was towed to harbour after losing power in choppy seas off Tiree.
Tobermory Lifeboat was launched to aid the stricken Silver Spray, which had suffered gearbox failure in force six conditions.
l A power cut hit Cairngorm mountain for five hours on Saturday, meaning ski lifts and the railway to the upper slopes could not be operated.
The area had been hit by whiteout conditions and 60mph winds on Friday. Services had also been stopped for two days earlier last week when blizzards struck on Monday.