SATELLITES, a nationwide radar network and the world's most powerful general purpose computer are part of the Meteorological Office's weather prediction system.
But the Met Office has a rival capable of greater accuracy in forecasting thunderstorms and flash floods . . . a rain gauge, not dissimilar to the type used by thousands of primary schools throughout the country.
The Met Office's current flood warning system, Frontiers, provides forecasts up to six hours ahead, but the radar scans areas five kilometres square, often too large to pick up small thunderstorms like those that left large swaths of southern England under water earlier this month.
The National Rivers Authority flood centre for London has found it inferior under certain circumstances to a rival and more basic system that uses traditional water gauges.
Bryony May, flood warning hydrologist at the NRA Thames Region Flood Warning Centre, said: 'We don't find Frontiers very reliable for predicting thunderstorms. It can often be misleading and is unable to pick them out.'
Instead a system devised by the Institute of Hydrology in Wallingford, Oxfordshire, which uses water gauges, is proving more successful.
Dr Duncan Reed, of the IoH's flood section, said: 'Conventional rain gauges are better at measuring the intensity of rainfall than radar.'
A Met Office spokesman, Barry Parker, conceded that 'small-scale rain storms' sometimes slipped through the radar network.
'We would love to have rain gauges all over the country but it would be too expensive.'Reuse content