WMOD00302 ‎(2)‎

• Contract/Permit #: 1-07-81-V0169
• Title: Development of Contingency Plans and Scientific Background Studies for Applying Weather Modification During Drought Periods in Utah
• Date: 12/1/1982
• State: UT
• Weather Modification - Doc Type: Report

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cloud at the proper ~empera~ure allowed seec1ng effects to
occur nearer the seeding location. In this case, seeding
increments of about 0.2 mm/hr occurred to the east of the
Grouse Creek Mountains, while the maximum effect occurred
in the Raf~ River ~ountains. In spite of the upwind displacement
of seeding effec~s rela~ive to ground-based seeding, blowover
of effects into Idaho also occurred.

It should be remembered in viewing these and subsequent
modeling runs that results apply only for the meteorological
condi~ions used in the model. Different winds or temperatures
oould result in different values and locations of the increment.
However, ~he rawinsonde da~a used for input were considered
representative.

In terms of logistics, the sparse population of the region
argues against ground-based seeding. Aerial seeding can be.
done on several of the Victor Airways upwind of the seeding
area, and minimuw. alti~ude requirements are not restrictive.

Based on these considerations, an aerial standby seeding
program is recommended. The base of operations could be Salt
Lake City, which has excellent instrument landing facilities.
Plight time from Salt Lake City to the seeding area should
be 45 ~inutes to an hour. Personnel should include a meteorologist
and a f~ll-time pilot. Some cost savings could be realized
by using an on-call pilot. However, considering the one hour
flig~t ~o the seeding area and the one to two hour lag required
for pilot notification and preparation, seeding opportunities

could be missed.

Since no weather observations are made near

t~e program area, a part-ti~e weather observer living in the
area, say Park Valley, should be used.

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