Short duration rain events are predicted to intensify during the summer months in the southern United Kingdom, reports a Letter published online in Nature Climate Change this week. This predicted increase means more events would exceed the Met Office and Environment Agency Flood Forecasting Centre guidance threshold for serious flash flooding.
Elizabeth Kendon and colleagues used a model typically employed for weather forecasting to investigate hourly rainfall changes in the southern UK. The model’s high resolution - 1.5 km grid spacing - allows projections of rainfall events and intensities on an hourly timescale.
The model confirmed projections from a coarser resolution model and previous findings of winter rainfall intensification. However, the coarser model was unable to project changes in summer downpours due to warming, which the higher resolution model was able to predict using accurate representation of local storm dynamics.