February was the wettest month of a winter characterised by an unusual combination of dry and mild weather, with the UK as a whole registering near average rainfall. It was particularly wet in southern Scotland and northern England but drier than average in Northern Ireland, which had its driest winter since 1970/71.
River flows were generally in the normal range after the winter characterised by substantially below average flows across most of the country. Winter mean flows in Northern Ireland, Wales and south-west England were among the lowest on record.
The assessment is contained in the latest monthly hydrological summary for the UK, the most authoritative analysis of water resources status in the country. The monthly summaries are produced by the National Hydrological Monitoring Programme, operated by the Centre for Ecology & Hydrology in conjunction with the British Geological Survey.
Although groundwater levels rose in nearly all of the index boreholes during February, levels remained below normal throughout most of the Chalk, but less so than at the end of January. Reservoir stocks increased throughout the UK, in some cases substantially, providing welcome replenishment during a notably dry winter. Overall stocks for England & Wales were as expected for the late winter, though some impoundments in Northern Ireland and south-west England remained well below average.
February 2017 river flows in the UK. Green indicates bflows in the normal range.
Summary author Simon Parry from the Centre for Ecology & Hydrology said, "With below normal groundwater levels and some substantially below average reservoir stocks, the weather over the next six weeks is likely to be influential in the outlook for water resources for the summer half-year."
The monthly summary is a look back at hydrological events occurring in February 2017. Latest information on flood warnings is provided by the Environment Agency, Natural Resources Wales and Scottish Environment Protection Agency (flood warnings for Northern Ireland are not available).
The Centre for Ecology & Hydrology jointly operates the National Hydrological Monitoring Programme (for the UK) in conjunction with the British Geological Survey. NHMP scientists produce the UK Monthly Hydrological Summary which assesses rainfall, river flows, groundwater and reservoir levels. They also operate the UK’s National River Flow Archive.
The NHMP also has a remit to analyse major flood and drought events in the UK and analyse long-term trends in UK hydrological data. The UK Monthly Hydrological Summary is normally published on, or before, the tenth working day, of the following month. A Hydrological Outlook for the UK is also available, and is updated monthly. The latest Outlook can be viewed here.