WMOD00286 ‎(3)‎

• Project Name: Colorado River Basin Pilot Project
• Title: Comprehensive Atmospheric Data Report 1974-75 Season - Volume I
• Date: 8/31/1975
• Weather Modification - Doc Type: Report

3) 1100 MST January 31, 1975 - 1100 MST February 6, 1975
Seeding operations were suspended on the basis that the 10-day
precipitable water accumulation was in excess of CRBPP suspension
criterion of 4. 00 inches of precipitable water for the existing snowpack.

4) On March 13, 1975 the Durango staff of EG&G, INC.
recommended to the BuRec that seeding operations be suspended, based
upon the 24-hour forecast of O. 50 inches of precipitable water upon an
existing snowpack of 118 percent and a 7-day total of greater than 4.00
inches of water equivalent of precipitation. It was likely that the addit-
ional forecast precipitation would induce many avalanches to slide in the
Wolf Creek area. This request was denied.

5) 1100 MST April 11, 1975 Seeding operations were suspen-
ded for the duration of the season when the snowpack (water content) at
Wolf Creek Pass IE exceeded 150 percent of the long term average
snowpack for the April and May period of operations.

e

3. 4 RECOGNITION AND FORECASTING
The weather' forecasting and analysis center, as established e
during the first operational season, was continued during the 1974-75
operating season, manned by two fulltime, professional meteorologists.
The raw data inputs included the information received via the Service
"A" long-line teletype network (i. e., the hourly aviation surface
weather reports) and the Service "C" long-line teletype network, which
provided the upper-air information and the synoptic surface reports.
The National Facsimile circuit (NAFAX), which provided data from the
National Meteorological Center, was an integral part of the operation.
Proj ect meteorological information from three high- mountain sites,
and seven remote generator site locations supplied surface wind, temp-
erature, humidity and precipitation data in and near the target area. In
addition, the time-sharing computer service furnished by the Bureau of
Reclamation provided other specialized information.

During the 1974-75 operating season, from two to four collection
platforms in the target area provided access to precipitation data through
the Earth Resources Technology Satellite (ERTS). This precipitation e
data was accessed primarily on experimental days through the time-

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