The Met Office has issued a weather warning for Derry for Thursday.
The warning is a yellow status weather alert for heavy rain.
The Met Office's Chief Forecaster said: "Heavy showers on Thursday afternoon and evening will produce torrential downpours in places. Some areas will see 10 to 15 mm of rain falling within an hour, with as much as 20 to 30 mm possible over three hours. As is often the case with showers some areas will miss the heaviest seeing only small amounts of rainfall."
The weather warning is valid from 12p.m. to 7p.m. on Thursday.