The Environment Agency has identified Todmorden and other communities along the River Calder and its tributaries – including Walsden, Eastwood, Mytholm, Hebden Bridge, Mytholmroyd, and Luddenden – as being vulnerable to the problem.
Efforts are now being made to raise awareness of the risks and other home safety issues and an event will be held at Todmorden Central Methodist Church on Thursday from 9.45am to 2pm.
Flash floods can strike with little or no warning and at their
most forceful can move rocks, tear out trees, sweep away vehicles and destroy buildings and bridges.
Recent flash floods in steep river catchments, such as Boscastle, in Cornwall, in 2004 and Helmsley, in North Yorkshire, in 2005, showed the risk to life that could arise during such floods.
After the 2007 floods, the Pitt Review recommended the Environment Agency should develop its tools and techniques for predicting and modelling river flooding, taking account of extreme weather.
Claire Fyfe, agency flood incident management officer, said: "Many people in the area are aware of the problems and distress which can be caused by flooding, as we again saw a few weeks ago.
"Thankfully extreme flash floods, such as those that affected Boscastle in Cornwall and Helmsley in North Yorkshire in recent years, are rare in this country but when they do happen they are highly dangerous and destructive, so being prepared can save lives.
"We want to encourage everyone to come along to the home safety event in Todmorden to find out more about keeping themselves and their family safe.
"We also will be encouraging people to take other steps to be prepared, such as registering for the Environment Agency's free Floodline Warnings Direct service, where this is available, and having a flood plan."
More information about flooding and flood warnings is available by logging on to www.environment-agency.gov.uk or by calling the 24-hour Floodline service on 0845 988 1188.