February was a truly remarkable month in hydrological terms, with three named storms (‘Ciara’, ‘Dennis’ and ‘Jorge’) and record-breaking river flows bringing widespread, protracted and severe flooding. The greatest rainfall anomalies (more than 350% of long term average) were over upland areas of northern and central England and in Wales, and for the UK as a whole it was the fourth wettest month on record (in a series from 1910). New peak flow, daily mean and monthly mean maxima were established on numerous rivers in England, Wales, Northern Ireland and southern Scotland – the extent, duration and magnitude of high flows across England contributing to the highest recorded monthly mean outflow (of any month, in a series from 1961). Three people died in storm-related incidents, hundreds of thousands of homes lost power and there was widespread travel disruption. Over 3,000 properties were flooded, with northern England, the west Midlands and south Wales the worst affected areas, and on the 16th, there were more live Flood Warnings and Flood Alerts in England than on any other day (in a record from 2006). Reservoirs were near capacity across the UK, and groundwater levels rose in all but two of the index sites, with more than half of the sites ending the month exceptionally high. The risk of surface and groundwater flooding from further rain on fully wetted soils remains, and damaging flows in large catchments continued into March.
We have also published a briefing note to highlight some of the key points from the monthly Hydrological Summary, and to provide some additional context beyond the space and format constraints of the Summary. Neither the Hydrological Summary nor this Briefing Note provide a fully comprehensive review of the severity of the February 2020 floods.