The Met Office has issued a yellow weather warning with a likely chance of flooding across parts of Grampian.
Outbreaks of heavy showers are expected in the Cairngorms and Ballater areas.
The alert will come into force at 9pm on Thursday and last until 9am on Friday.
Public transport may be affected, with journey times taking longer due to spray and flooding on roads.
A statement said: “Following recent wet weather, another band of heavy rain will arrive on Thursday evening and continue overnight, easing on Friday morning.
“20-30mm of rain is likely to fall within 9-12 hours, and this, combined with snowmelt from the hills, will lead to some rising river levels, and the chance of localised flooding.”