South Dakota has declared April 17-21 as Severe Weather Awareness Week. In order to observe this, Union County will be conducting siren tests in all municipalities at 1:45 p.m. on Thursday, April 20. Union County Emergency Manager Jason Westcott urges residents to be weather aware. “If you hear the siren, go inside,” Westcott said. “Go inside, seek shelter and grab your [cell] phone or use a TV…