WMOD00284

• Applicant: Thompson, J.R., G.W. Wilderson, and D.A. Griffith, North American Weather Consultants
• Sponsor Name: USBR
• Title: Cloud Seeding Data Collection, and Analysis Assoc. with the Colo River Augmentation Demonstration Program
• Prepared For: USBR, Divison of Atmospheric Research
• Prepared By: Thompson, Wilderson, Griffith
• Date: 12/1/1987
• State: AZ
• Weather Modification - Doc Type: Scientific Study

3.1.4

Synopsis of storm Episodesr Mid-Januarv to
Mid-March, 1987

Using the above parameters plus the availability of project
aircraft flight data and the Skywater 5-cm radar data (for
cloud structure and top measurements) the episodes were selected
and then ranked for their general interest as case studies.
In making the selections, usually the presence of SLW was
the first consideration, followed by precipitation, number
of aircraft flights, etc. with this scheme a total of 16
episodes were identified. There were three other periods
in late January that had brief recordings of 8LW but other
measurement systems were not operated, e.g., the aircraft
did not fly or the radiometer or radar was not operating,
These were not included as episodes.

A description of each of the episodes is contained in,
some detail in Appendix A. Included is a summation of the
synoptic weather pattern (along with the Medina weather type
which the pattern best characterized), the character of the
SLW measurements and the precipitation pattern and amount
during the episode. The episodes were ranked in regard to
their general interest and possible seeding potential (from
the standpoint of 8LW availability) starting with the synoptic-
-scale stratiform cases (88-1 through 8S-10), then the three
synoptic-scale convective cases (where SC-1 would be of more
interest than some of the lower ranked "8S" episodes), and
finally, the three mesoscale convective episodes (MC). There
were no mesoscale stratiform (MS) episodes during the mid-January
to mid-March period.

3-9

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