Daventry people have been asked to submit their photos and accounts of the weekend's severe weather after reports of a 'tornado' in the town.
Sunday's storm, which damaged cars in Lang Farm and Middlemore, is being investigated by the Tornado and Storm Research Organisation (TORRO) - a privately supported research body founded in 1974.
An initial report on the thunderstorms is expected to be presented at TORRO’s annual autumn conference in October, at Oxford Brookes University.
"Large hailstones and a funnel cloud have been reported in the Daventry area," said Jonathan Webb, the director of the TORRO Thunderstorm Division.
"We will welcome any accounts of the hailstorm and photographs of the hailstones (with location and time), including damage, as these will be invaluable to our investigation.
"Any information on strong local winds or lightning damage will likewise be of great help with our research. I can be emailed directly at email@example.com or firstname.lastname@example.org.
"Alternatively, a dedicated report online form can be found on our website here."
According to TORRO, based on a 30-year average, 33 tornadoes occur each year in the UK.