This summer's unusually wet weather means there is a higher risk of flooding in autumn and winter, the Environment Agency and Met Office has warned.
The wettest April to June on record, and further wet weather in July, September and October, has left river levels full, the ground saturated and exceptionally high ground waters in some areas, the agencies said.
The emergency services and householders are being advised to be prepared for flooding, which, because of the wet conditions, could hit with relatively small amounts of rain.
"This year our flood defences have protected over 119,000 properties, but we cannot prevent flooding entirely," said the Environment Agency's Paul Mustow.
"With one in six homes at risk of flooding, the most important step people can take in protecting themselves from the worst impacts is to find out if they are at risk, and sign up to the Environment Agency's free flood warnings service.
"As winter approaches, we'd encourage everyone to take this one step to help protect themselves from what is recognised as the country's number one natural hazard."
Sarah Jackson, the Met Office's chief adviser to the Government, said: "We are heading into the winter period which is traditionally the wetter period of the year in the UK.
"Because the ground is so wet, if we do have any prolonged heavy rainfall in any part of the country, there is going to be heightened risk of flooding.
"We recommend that everyone keeps up-to-date with the latest forecasts and warnings in periods of wet weather to be prepared."
More than 1.1 million people are signed up to receive Environment Agency flood warnings - which can be sent by email, text, or a message to a landline or mobile phone.
This summer, more than 100,000 households were warned of potential flooding, giving people essential time to protect their homes and possessions.
Households and businesses can check their flood risk and sign up to receive free flood warnings at www.environment-agency.gov.uk/flood .