WMOD00375

• Contract/Permit #: 0-07-81-V0144
• Project Name: South West Drought Project
• Title: Operational Weather Modification - Volume I: A Seminar Series
• Date: 9/1/1981
• State: OK
• Weather Modification - Doc Type: Report

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FIG, 2. [965-73 total J h rainfall frequencies and amounts
for the Dodge City {ODe} area.

The design of an opE!rational or experimental cloud seeding
project should consider the severe weather problem as it relates
to human activities and land usage. Thus, the restrictiveness
of the shutdown criteria may vary from one location to another.
Five criteria which vary according to the type of watch and the
areas covered by the watch have been developed in anticipation
of a variety of design requirements. Watch information drawn
from the eight areas that surround the operations area. shown in
Fig. 1 enter decision making in two ways. First, if a watch is
issued for areas upwind from the Dodge City area, operations
may be suspended for concern that severe weather watches will
soon be issued for the project area and/or that severe weather
will move in later in the day. Secondly, if a watch is issued
for areas downwind from the Dodge City area, operations may be
shut down for concern that seeding material may drift downwind
into the valid watch area and interact with storms there. Thus,
in some situations, weather conditions in the total area (Dodge
City plus eight surrounding areas) might need to be monitored.
The five criteria fOl:: the severe weather related suspension
of cloud seeding operations are as follows:
1) Total area watches - This is the most conservative approach.
In the event that a severe weather watch of any kind is issued
either within the DDC area or within the surrounding areas,