The Scottish Environment Protection Agency (Sepa) has issued 12 flood warnings and eight flood alerts.
Some areas have also been marked for flood alerts where flooding is possible.
Sepa hydrology manager Marc Becker said: "We would encourage people in the areas potentially at risk to remain vigilant and be mindful of the conditions in their locality and when travelling.
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Daily Dose, a short summary of the day's election campaign stories.
Atlantic frontal systems will spread rain across the UK overnight, turning to showers as the night goes on.
And we’re off! All aboard the big-blue-battle-bus, union flag fluttering and a typically dry election slogan stretching across the side.