Monthly precipitation totals were mostly within the normal range across the UK in January but sustained frontal rainfall, often augmented by snowmelt, in the final week of the month triggered a further episode of extensive floodplain inundations. The April 2012-January 2013 period is the wettest on record for England & Wales.Snow at CEH's Wallingford HQ

The analysis is contained in the latest monthly hydrological summary for the UK, covering the month of January 2013. The monthly summaries are produced by the National Hydrological Monitoring Programme, operated by the Centre for Ecology & Hydrology (CEH) in conjunction with the British Geological Survey.

Summary lead author Terry Marsh, from CEH, said, “After the wettest April-January on record for England & Wales, the water resources outlook is very healthy but many areas will remain vulnerable to both fluvial and groundwater flooding through the remainder of the winter at least.”

The latest Monthly Hydrological Summary for the UK gives details of:

  • Rainfall:  Notwithstanding the below average January total for England & Wales, the April-January rainfall is the highest for any 10-month sequence in a rainfall series from 1766 and the total for the winter half-year thus far (Oct-Jan) is exceptional.
  • Groundwater levels: With soils remaining close to saturation throughout January, aquifer recharge was again healthy, adding to the remarkable replenishment through much of 2012.
  • River flows: Northern Scotland apart, January runoff totals were generally close to, or above, average
  • Reservoir stocks:  most reservoirs benefited from exceptional inflows late in the month. The great majority of index reservoirs were close to capacity in early February but water quality issues (restricting the replenishment of some pumped storage impoundments) and planned maintenance have left some reservoir stocks below the late-winter average.

A PDF of the full 12-page UK Hydrological summary for January 2013 can be downloaded here.

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 published on, or before, the tenth working day, of the following month.

Additional information

Read the full January 2013 Hydrological Summary for the UK [PDF, 4.9mb] 

Hydrological summary archive - dating back to December 1988 

Details of the National Hydrological Monitoring Programme

CEH Blog: Filming at CEH's met site in Wallingford, January 2013

Datasets hosted by CEH: National River Flow Archive, National Water Archive and others

Media enquiries related to the Hydrological Summaries should be directed to the CEH Press Office. Our scientists can provide explanation and analysis of historic hydrological patterns, possible future scenarios under climate change and scientific understanding of the current situation. We are not able to comment on immediate operational issues.

If you wish to reproduce figures from the Monthly Hydrological Summary please respect the copyright credits contained within the document.

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