Sunday’s situation where Lyon County sets off the tornado warning sirens without a warning from the National Weather Service is a rare occurrence, and officials with both entities will meet next week to discuss it in more detail.
The Lyon County Emergency Communications Center made the decision to sound sirens in Emporia and Olpe after traveler reports of funnel clouds were confirmed by a Lyon County deputy near Plymouth. The Weather Service did not issue a warning. Lyon County Emergency Management Director Jarrod Fell says it made for a confusing afternoon.
Lyon County will sound the tornado warning sirens if one of three situations happen:
*Official warning from the National Weather Service
*TV confirmation
*Field reports from law enforcement, firefighter or emergency medical personnel
*TV confirmation
*Field reports from law enforcement, firefighter or emergency medical personnel
National Weather Service Warning Coordination Meteorologist Chad Omitt says there are three criteria for the Weather Service to issue a tornado warning:
*Radar signatures
*Storm environment
*Field reports
*Storm environment
*Field reports
Sunday only met one benchmark — field reports. Omitt says there was low-level buoyancy and steep lapse rates at the time of the funnels, which can lead to funnels or weak “landspout” tornadoes, but wind shear was weak. Storms also clustered quickly after they developed, ending any tornado threat.
Omitt also says Sunday’s situation was vastly different from the more traditional setup like what led to the Reading tornado a decade ago — or from the Harveyville tornado in February 2012, where a tornado touched down and lifted between radar cycles, killing one person in the process. He says features like landspouts or rope funnels, such as what was reported Sunday, are far too small to pinpoint even with radar at close range.
The Lyon County Emergency Communications Center has taken steps to alert the media in cases where the sirens are activated but no warning is issued.
