Residents in Angus, Dundee and parts of Perthshire and Fife are being warned of heavy rain and potential flooding.
The 18-hour yellow warning of rain comes into effect at 6am on Thursday and lasts until midnight.
The Met Office says up to 100mm could fall in some areas, which could bring travel disruption and result in communities being cut off.
Power cuts could also occur.
Flooding could cut off communities
Local residents are being warned that some communities could be cut off by flooded roads.
The warning covers an area from Montrose in Angus down to Dundee, as well as inland areas of Angus and Perth and Kinross, including Perth itself.
A small part of Fife is also inside the yellow warning area.
“Heavy rain is expected to arrive early on Thursday and then persist for much of the day,” the warning says.
“Whilst some snow is expected to fall initially over higher ground, this should tend to turn to rain which will then steadily thaw lying snow.
“30-50 mm of rain is likely to fall widely with potential peaks over hills of 70-100 mm.
“Rain will be accompanied by strong southeasterly winds.
“Further heavy rain is possible in similar areas on Friday but this aspect is currently unclear.”
Power cuts possible, says Met Office
The Met Office says there is a small chance that homes and businesses could be flooded, causing damage to some buildings.
Where flooding occurs, there is a slight chance of delays or cancellations to train and bus services, while spray and flooding could lead to difficult driving conditions and some road closures
Power cuts and loss of other services to some homes and businesses is another slight possibility.
It further warns there is a small chance that some communities will become cut off by flooded roads adding there is a small chance of fast-flowing or deep floodwater causing danger to life.