Observations of a tornadic supercell over Oxfordshire using a pair of Doppler radars

On 7 May 2012 between approximately 1500-1600 UTC (45pm BST) a small tornado was reported by a number of observers in Witney, Kidlington and Bicester in Oxfordshire (see White 2012; Jones 2012; many more details and photographs/videos can be found by searching the world wide web). The strong winds associated with this tornado led to damage of trees, roofs and streetlights. Damage site investigations, conducted by members of the Tornado and Storm Research Organisation (TORRO: www.torro.org.uk), subsequently revealed a 17km-long track of intermittent damage to the north and west of Oxford (S. P. Culling, personal communication, 2012). In addition to the strong winds in the tornado itself, heavy precipitation and reasonably large hailstones (≈ 1-1.5cm diameter) were also reported. Thunder and lightning were also associated with this storm, and lightning strike locations, as detected by the Met Office Arrival Time Difference Network (figure 1), clearly show its progression throughout the afternoon as it tracked over the Cotswolds and Oxfordshire, and on into the home counties.