The Met Office has issued a yellow warning for heavy rain through to Friday (29 October), in Preston.
It is thought that rain may cause flooding and disruption to travel, with a small chance that homes and businesses will be affected, causing damage to some buildings.
The Met said there is a small chance of fast flowing or deep floodwater causing danger to life, and where flooding occurs, there is a slight chance of delays or cancellations to train and bus services.
An original weather warning was issued covering Cumbria and North Lancashire – but as of Thursday (28 October) has now been extended to include Preston and parts of South Ribble.
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They warned there is also a small chance that some communities will be cut off by flooded roads, with a slight chance of power cuts and loss of other services to homes and businesses.
It is also thought that spray and flooding could lead to difficult driving conditions and some road closures.
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