WMOD00594

• Title: Investigations of Winter Mountain Storms in Utah during the 1987 Utah/NOAA Field Program
• Date: 1/1/1990
• State: UT
• Weather Modification - Doc Type: Report

listed above were developed. The objectives allowed for the fact

that, no cloud seeding -was to be conducted in the 1987 -;esearch
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program and only natural clouds were to be studied.

In 1987 two kinds of field studies were undertaken to collect

data relevant to these obj ecti ves.

with respect to the first

objective concerned with the transport of silver iodide seeding
material, ~ele~~~~ield ~a~~ came from tracing sulfur hexafluoride
(SF6) gas, release~ f:.:o~ _ a potential ground generator site, by
aircraft in the vicinity_ o_~~~he Tushar lIt_ns and using surface-based

samplers in the upwind valley and on the slopes of the mountains.
With respect to the second and third objectives, concerned with the
supercooled liquid water and with the precipitation processes,
trajectories, and efficiency, relevant field data came from remote

sensing instrumentation including K.-band radar, a microwave
radiometer, and a polarization diversity lidar, and from ground
based instrumentation for measuring supercooled liquid water and for

observing the microphysical characteristics of precipitation
particles. Supporting data for all of this work were obtained with

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rawinsondes launched from two sit~s, with precipitation gages, from

the National Weather Service, and from the GOES-6 satellite.

Numerous details of operations during the 1987 field program

are contained in the 1987 Field Operations Report (Long, 1987a).

For this reason, descriptions of instrumentation and operational

procedures, in this report, will be brief and in summary form.
The results of analysis of data collected in 1987 are contained
in reports of the individual participating groups submitted to the

utah Oivision of Water Resources. Each of these reports covers a

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