Planned Weather Modification and the Severe Weather Threat in the Central High Plains

Abstract

Operational and experimental convective cloud-seeding projects are often planned without regard to the number of seeding-opportunity days that can be lost because of the need to suspend operations during the threat of severe weather. June daily rainfall, severe storm and tornado watches, and observed tornadoes within a hypothetical (proposed) operational area over southwest Kansas were compared within the context of five procedures for severe weather related operations suspensions. These procedures varied in the restrictions placed on operations. The results show that anywhere from 45–87% of the June rain can fall when operations have been suspended. The length of a scientific seeding experiment could be increased anywhere from 45–426%. Finally, 46% of the tornadoes occurred when there were no concurrent tornado watches. This failure rate is so large that severe weather watches may not be useful for operations suspension procedures.