The hardest hit areas are Dumfries and Galloway and portions of Ayrshire. More than 100 homes were evacuated and firefighters using boats rescued some stranded residents, the BBC reported.
More than 2 inches of rain fell in the area, which also experienced damaging winds as high as 80 mph.
More than 40 homes were evacuated in the village of Kirkconnel alone, the BBC said.
No deaths had been reported but widespread power outages accompanied the flooding, officials said. Several main roads remain closed and commuter train service has been shut down in the area.
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