The trail of damage is increasing across South Australia as severe thunderstorms redevelop over a large area for the second day running. In the past day or so storms have caused pockets of damage, but are about to leave a more widespread trail. Monday and Tuesday night's storms produced wind gusts of 120km/h in Maree, 109km/h in Roxby Downs, their strongest in more than two years. The storms in the far north last night travelled in a line through the Flinders, Riverland and Murraylands, where lightning, strong winds and flash flooding made quite a mess. Thousands of homes were left without power and a few were even unroofed. Peterborough in the Mid North gained 39mm of rain in about an hour. Today's widespread storms look to have just as much vigor, with a chance of striking some of the same towns again. Mt Gambier gained 12mm at lunchtime. Damaging wind gusts in excess of 100km/h are likely, strong enough to bring down trees and powerlines and to unroof buildings. Flash flooding and large large hail are also a chance. Today's main storm area is north and east of Adelaide but it will move well east of Adelaide this evening as a cooler, drier westerly change moves through.