The challenge, Trapp said, is the same one that all forecasters face: A forecast depends on the data available.
Tornado prediction is an evolving science
Tornado emergency declared minutes before tornado reached the city
POSTED: 02:29 PM MDT May 21, 2013 UPDATED: 06:21 PM MDT May 21, 2013
Copyright 2013 by CNN NewSource. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.