There are four layers show showing the forecasted river flash flood impact levels forecasted for the following four lead time windows, each are summarised at the catchment level:
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This forecasted impact level in each river catchment is shown as one of four levels: low (yellow), moderate (orange), high (red) and severe (purple). The impact level is estimated by intersecting using a risk matrix to intersect a flash flood hazard forecast with static exposure data ( of population and critical infrastructure) on a risk matrix. Both the flash flood hazard and the exposure data are split into three categories to create the risk matrix (see an example in the left hand side of Fig. 1).
Methodology Overview
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