WMOD00311 ‎(2)‎

• Title: Climatologies and Intercomparisons of Rawinsonde Data Collected During Winter Storm Periods in Utah
• Date: 8/1/1980
• State: UT
• Weather Modification - Doc Type: Report

2. BACKGROUND ON THE UTAH WINTER SNOWPACK AUGMENTATION PROJECT

The Utah winter snowpack augmentation project began opera-
tional seeding in January 1974 and recently completed its
seventh consecutive winter-season of operations. The project
is operated under the joint sponsorship of the Utah Water
Resources Development Corporation (a private, non-profit group)
,and the State of Utah, Division of Wa ter Resources. As the
project title implies, the. purpose of the seeding project
is to increase the winter snowpack in the high yield areas
of the mountainous terrain ,in portions of Utah. The project
target areas which are shown schematically in Figure 2.1,
cover over 10,000 square miles of mountain and valley watershed
and include all or portions of more than half of the counties
wi thin Utah. Typically cloud seeding operations begin with
the onset of winter storminess (mid November) and end in early
spring (mid April).

Approximately 70 manually operated cloud seeding generators
are located at strategic ground sites within and adjacent
to the target areas. When storm systems approach the area
seeding is initiated by telephoning a generator operator at
the locations desired, provided certain seedabi Ii ty criteria
are met. These seedability criteria are determined from analyses
of the project operated rawinsondes at points within the target
and/or from the NWS sites outside of the target.

In March of 1976, NAWC prepared a preliminary master
plan for a continuing weather modification program in Utah.
This study was conducted without funding and was necessarily
limited in scope but it did suggest that certain aspects of
project operations should be examined in more detail to upgrade
the project. With the prospect of a continuing and expariding
2-1

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