Submitted by Steve Turner on
April was a generally dry and settled month, although bookended by more stormy conditions. Rainfall was notably below average across much of the UK, particularly in eastern England, whilst it was above average in Northern Ireland and Wales with the majority of this rainfall delivered by storm ‘Hannah’ at month-end. April mean river flows were below normal across much of the UK and notably low in some catchments draining western Scotland, northern England and the English Lowlands. With a predominantly dry month and warm weather over the Easter weekend (temperature records were set in Scotland, Wales and Northern Ireland), Soil Moisture Deficits (SMDs) increased across much of the UK and remained drier than average for the time of year. Groundwater levels were below normal in eastern England, notably so in East Anglia, and generally in the normal range elsewhere. Stocks in most reservoirs declined during April, substantially so in some impoundments in northern England, and were more than 10% below average in Northern Command Zone, Derwent Valley and Bradford Supply. Despite overall reservoir stocks for England & Wales being near average, dry soils and notably low groundwater levels (particularly in eastern England) caused a contracted streamflow network, localised agricultural stress and water restrictions in some areas. River flows in parts of eastern England were comparable to seasonal low flows recorded in previous drought years (e.g. 1976, 1997 and 2011). With the groundwater recharge season over, river flows and groundwater levels are likely to remain persistently low. With the latest seasonal rainfall forecast favouring slightly below average rainfall, increased vigilance will be necessary to avert further restrictions and localised water resource pressure through the summer.