Common Warnings Framework for flood risk in England and Wales – improving communication language for flood risk and how ensembles and AI may provide more objective risk assessment

Risk can be defined as the likelihood of a certain level of impact occurring. The Flood Forecasting Centre (FFC) communicate the flood risk in England and Wales using a risk matrix. This risk matrix compares the likelihood and impact to conclude the overall flood risk. This is communicated through the Flood Guidance Statement (FGS), which is issued daily. A similar risk matrix is used across the UK, including by the UK Met Office (UKMO) and the Scottish Environment Protection Agency (SEPA). However, currently there are differences in how the risk matrices are used and communicated. Recent storm events, such as Storm Bert, have highlighted the importance of clear and consistent messaging of risk across events and organisations to ensure that users of the risk matrix make appropriate decisions.

To address this issue, the FFC have been part of the Common Warnings Framework (CWF). This has included working alongside the UKMO and SEPA, as well as Environment Agency (EA), Natural Resources Wales (NRW) and Department of Infrastructure Northern Ireland (DfI). The research work, led by the UKMO, has been based around the Common Alerting Protocol (CAP). CAP has been used as a guide on how likelihood and impacts can be communicated. The main outcome of this work has been to agree a commonality in communicating flood risk. This will provide greater clarity, consistency and visibility around flood risk for emergency services, government and the public. The FFC have established a taskforce this year to deliver the changes to the flood risk matrix in time for winter 2026/2027.

Alongside the Common Warnings Framework, the FFC are exploring making more use of ensemble data. Working with the UKMO and EA, this has involved using meteorological ensemble data to drive hydrological ensemble output. A primary aim is to make the assessment of the likelihood of flooding impacts more objective and consistent during and between events. This is to improve flood incident management action. This approach has been trialled this winter with preliminary results expected during 2026.

This presentation will explain the upcoming changes to the FGS flood risk matrix. It will highlight how the flood risk matrix has evolved with time, the benefits the changes will make and how the changes link to the output from the ensemble trial. This includes looking at how useful ensemble based meteorological and hydrological summary tools may be for flood forecasters and decision makers, with the overall aim to improve the communication of risk. With more ensemble data becoming available this does create additional challenges in communicating risk. This presentation will also discuss the work the FFC has started in this area, looking at what AI can offer around impact assessments and communicating risk.