August was an unsettled month, feeling autumnal at times and lacking many hot summer days. Most areas of the UK received a combination of light showers, persistent rainfall from frontal systems and torrential downpours from thunderstorms. Rainfall anomalies were most significant along the south coast of England, with more than double the average rainfall received across large areas, and approaching three times the average in some locations. Daily rainfall totals that were similar to average monthly totals triggered flash flooding that impacted properties and transport networks in a number of localities. River flows in August were seasonally high in the wettest southern areas of the UK (relative to average), but not of sufficient magnitude to cause extensive fluvial flooding.
Despite the wet weather across much of the aquifer outcrop areas of southern England, groundwater levels continued their seasonal recessions in most boreholes in England and Wales. Reservoir stocks increased substantially in Northern Ireland, with overall stocks there, and in western Scotland and northern England registering as significantly above average. Soil moisture deficits generally decreased in August and were below average across the aquifer areas of southern England. As a result, groundwater recharge through autumn is unlikely to be delayed in these areas and, combined with near average reservoir stocks for England and Wales, indicates that the water resources outlook remains healthy.
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