Heavy and thundery downpours over east Devon, with flooding and travel disruption...
An area of low pressure and associated frontal system over south-west England at 0000 UTC on 30 October 2008 (see chart below), resulted in localised but intense hail/thunderstorms over east Devon.
Properties and roads in the Ottery St. Mary and Feniton areas were flooded, and the main road (A30) between Honiton and Exeter was closed.
Synoptic situation at 0000 UTC on 30 October 2008
Rainfall values and return period information below for Ottery St. Mary, Kings School.
Rainfall values and return period information below for Dunkeswell.
The graph below shows the hourly rainfall totals at Dunkeswell between 0900 UTC on 29 October 2008 and 0900 UTC on 30 October 2008.
The radar animation below uses 15-minute 1/2/5 km composite data between 2100 UTC on 29 October 2008 and 0300 UTC on 30 October 2008.
Please note: The empirical relationship between radar reflectivity and rainfall rate is fixed whereas in reality this is highly dependent on precipitation type and is very different for rain and hail.
Grahame, N., Riddaway, B., Eadie, A., Hall, B. and McCallum, E., 2009: Exceptional hailstorm hits Ottery St Mary on 30 October 2008. Weather, 64, 256-263.
Photographs from Ottery St. Mary below, reproduced by permission of Margaret Bargmann.