Yellow warning of rain, 21 January 2008

The example below details an event that happened in northwest England. It would have generated a yellow warning of rain with the new warning service.

Rain Warning Yellow Weather situation on 21 January 2008

Weather

An area of low pressure with bands of heavy rain moved eastwards from Northern Ireland to Northern England. It was the latest in a series of rainfall events that had affected the area in the preceding weeks. Although rainfall amounts were relatively modest, impacts occurred as the result of already almost saturated ground and raised river levels.

Combined rainfall totals for 20 and 21 January included:

Stoneyhurst (Lancashire)57mm
Carlisle (Cumbria)42mm
Rochdale (Greater Manchester)41mm

This particular example has been chosen to illustrate what can happen when a relatively modest amount of rain falls on land that has been brought to virtual saturation by well above average rainfall in the preceding weeks. The period leading up to the event had been very wet with roughly twice the average rainfall for January.

Impacts

A flooded street 2 A flooded street

  • The West Coast Mainline railway route was closed for a time between Preston and Lancaster.
  • Motorists were urged not to travel across Cumbria due to surface water flooding on many key roads with resultant closures. Several schools in the county were closed due to approach roads becoming impassable.
  • A mother and baby were rescued from a stranded car in Swinton, Greater Manchester.
  • Various livestock were rescued from a flooded farm near Rochdale, Greater Manchester.
  • Some minor rivers flooded and there were numerous localised surface water incidents.
  • The Irwell flood basin in Salford was opened and successfully utilised.
  • The Environment Agency posted various Flood Warnings across parts of the northwest.

Warning Assessment

Based on the new warning system the following assessments would have been made:

  • Likelihood - medium
  • Impact - low

This would have resulted in a yellow warning for rain:

Yellow Warning

Last updated: 26 March 2012