The National Weather Service has confirmed the damage to the Viola area April 27 during what is being termed the Super Tornado Outbreak was in fact an EF-1 tornado.The storm left two residents of a trailer on Highway 108 with noncritical injuries after the trailer was overturned by high winds. The storm also did significant damage to a nearby farm and splintered and toppled utility poles up and down Highway 108.National Weather Service investigators believe the tornado was an EF-1 with speeds from 105 to 110 mph. EF-1 stands for Enhanced Fujita Scale, named after the scientist who came up with the system of tornado measurement.